Descriptor: "GAMMA-RAY" / Topic: astrophysics - Searchworks@Jio Institute Digital Library Search Results

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88 results on '"GAMMA-RAY"'

1. Probing for Extended Gamma-ray Emission Within and Beyond the Virial Radius from the Coma Galaxy Cluster

Author: Stevenson, Thomas Brandon
Subjects: Physics, Astrophysics, Coma, Galaxy Cluster, Gamma-ray
Abstract: Galaxy Clusters (GCls) are the largest known virialized objects in the Universe. About one-third of GCls exhibit an extended radio halo associated with a population of nonthermal electrons emitting synchrotron radiation in a microgauss level magnetic field. The cooling time for the nonthermal electrons is about two orders of magnitude below the diffusion time needed to explain the radio halo, indicating that the electrons are created locally. The electrons may either be accelerated directly in the turbulent cluster medium or created as secondary products from nonthermal protons colliding with the intracluster medium. Observed gamma-ray emission can therefore resolve the contribution from these two mechanisms. Despite the empirical and theoretical motivation for the existence of gamma-ray emission from GCls, so far it remains undetected. In this talk VERITAS observations are used to analyze a 6x8 degree field of the Coma galaxy cluster and evaluate the existence of possible extended gamma-ray emission. To achieve this, a method is developed which utilizes cosmic rays as a calibration source to determine a background measurement across the full field of view. The resulting excess demonstrates a small significance of 2.7 sigma in the central 1.5 degree radius of the cluster. This observed central excess, while alone is not significant, has an angular extent in agreement with simulations and corresponds to a similar significance level seen by Fermi-LAT in the same region, and hence it is worth further investigation by VERITAS and future instruments such as CTA.
Published: 2020

2. Measuring the polarization of compact objects with the Compton Spectrometer and Imager

Author: Sleator, Clio
Subjects: Astrophysics, Compton telescope, gamma-ray, high energy astrophysics
Abstract: γ-rays are an indispensable probe of neutron star and black hole systems, some of the most extreme environments in our universe. The penetrating power of γ-rays allows us to probe deep within these often obscured systems. In particular, polarization measurements of neutron stars and black holes can give essential clues about γ-ray emission mechanisms, source geometry, and magnetic field structure where spectral, temporal, and imaging analysis fall short.The Compton Spectrometer and Imager (COSI) is one of the few γ-ray telescopes designed as a polarimeter. COSI is a wide-field balloon-borne soft γ-ray (0.2-5 MeV) telescope, and one of its main goals is to measure the polarization of γ-rays emitted by compact objects. As a Compton telescope, COSI is inherently sensitive to polarization: polarized photons preferentially Compton scatter orthogonally to their polarization direction. In May of 2016, COSI was launched from Wanaka, New Zealand, on NASA’s new super pressure balloon and flew for 46 days before the flight was terminated in Peru. The Crab nebula, Cygnus X-1, and Centaurus A are among the compact objects detected during the 2016 flight.A key step to performing imaging, spectral, and polarization analysis of the sources detected during the 2016 flight is to accurately simulate the detector response. To do so, I developed a detailed detector effects engine which applies the intrinsic detector performance to Monte Carlo simulations. With accurate simulations of the instrument in place, I developed a spectral analysis pipeline for sources detected by COSI. As needed for spectral analysis and polarimetry, I developed a background subtraction technique for broadband, persistent sources that utilizes the COMPTEL data space. I verified these new analysis methods using the COSI observation of GRB 160530A: after subtracting the background using the COMPTEL data space method and fitting the spectrum, the spectral parameters are consistent with those measured by another instrument.I used the COMPTEL data space background subtraction algorithm to fit the Crab spectrum, but concluded that the algorithm is limited in estimating the background accurately enough in cases where the source is background-dominated. I used simulations to assess the prospects for polarimetry of COSI’s observation of the Crab and inferred that we require a better mechanism of albedo radiation background rejection to perform polarimetry of this particular observation. I note that similar observations from the COSI instrument on a satellite platform would lead to more success in measuring the spectra and polarization properties of compact objects, and that the analysis methods developed in this work could be easily applied.
Published: 2019

3. From balloon to satellite: Measuring Galactic 26Al with the Compton Spectrometer and Imager

Author: Beechert, Jacqueline
Subjects: 26Al, Compton telescope, satellite, balloon, COSI, Astrophysics, Nucleosynthesis, Gamma-ray
Abstract: The Compton Spectrometer and Imager (COSI) is a 0.2-5 MeV Compton telescope designed for spectroscopy, imaging, and polarimetry. Like INTEGRAL SPI, the heart of COSI is comprised of high-purity germanium detectors with excellent energy resolution. COSI was originally developed as a balloon-borne instrument which flew for 46-days on a NASA superpressure balloon in 2016. The flight was a scientific and technological success: COSI detected and imaged the Galactic positron-electron annihilation excess at 511 keV, detected and placed an upper limit on the polarization of GRB160530A, detected the Crab nebula, and in a recent analysis, measured the 1809 keV decay signature of radioactive Galactic Al-26 with 3.7σ significance. The Inner Galaxy flux of Al-26 is reported as (8.6 +- 2.5) x 10-4 ph/cm2/s. This presentation will detail the Al-26 analysis, compare results to those from SPI, and outline the expected performance of COSI as a NASA Small Explorer satellite mission, slated for launch in 2027.
Published: 2022
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4. Perspectives on Gamma-Ray Burst Physics and Cosmology with Next Generation Facilities.

Author: Yuan, Weimin, Amati, Lorenzo, Cannizzo, John, Cordier, Bertrand, Gehrels, Neil, Ghirlanda, Giancarlo, Götz, Diego, Produit, Nicolas, Qiu, Yulei, Sun, Jianchao, Tanvir, Nial, Wei, Jianyan, and Zhang, Chen
Subjects: *GAMMA ray bursts, *WIDE field telescopes, *AFTERGLOW (Physics), *SPACE astronomy, *REDSHIFT, *ASTROPHYSICS
Abstract: High-redshift Gamma-Ray Bursts (GRBs) beyond redshift ${\sim}6$ are potentially powerful tools to probe the distant early Universe. Their detections in large numbers and at truly high redshifts call for the next generation of high-energy wide-field instruments with unprecedented sensitivity at least one order of magnitude higher than the ones currently in orbit. On the other hand, follow-up observations of the afterglows of high-redshift GRBs and identification of their host galaxies, which would be difficult for the currently operating telescopes, require new, extremely large facilities of at multi-wavelengths. This chapter describes future experiments that are expected to advance this exciting field, both being currently built and being proposed. The legacy of Swift will be continued by SVOM, which is equipped with a set of space-based multi-wavelength instruments as well as and a ground segment including a wide angle camera and two follow-up telescopes. The established Lobster-eye X-ray focusing optics provides a promising technology for the detection of faint GRBs at very large distances, based on which the THESEUS, Einstein Probe and other mission concepts have been proposed. Follow-up observations and exploration of the reionization era will be enabled by large facilities such as SKA in the radio, the 30 m class telescopes in the optical/near-IR, and the space-borne WFIRST and JWST in the optical/near-IR/mid-IR. In addition, the X-ray and $\gamma$ -ray polarization experiment POLAR is also introduced. [ABSTRACT FROM AUTHOR]
Published: 2016
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5. Spectral trends in the Very High Energy blazar sample due to EBL absorption.

Author: Behera, Bagmeet and Wagner, Stefan J.
Subjects: *BL Lacertae objects, *ACTIVE galaxies, *RADIO sources (Astronomy), *REDSHIFT, *CHERENKOV radiation, *ASTROPHYSICS
Abstract: The absorption of γ-rays in the intergalactic medium due to the EBL (Extragalactic Background Light) causes the observed blazar spectrum to be fainter and softer than their intrinsic state. It could thus be expected to see an effective spectral-softening trend with redshift. No such trend is evident in the sample of VHE blazars currently observed. To check which distributions of the properties of the parent blazar population could reproduce the observations, various simulations are done. The resulting subsamples that satisfy a generic detection criterion for the current generation of ACTs (Atmospheric Cherenkov Telescope) are checked to identify whether any inherent correlations (of spectral properties with redshift) are required to explain the current observations. [ABSTRACT FROM AUTHOR]
Published: 2008
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6. The redshift-dependence of gamma-ray absorption in the environments of blazars.

Author: Reimer, A.
Subjects: *REDSHIFT, *GAMMA rays, *PHOTONS, *LIGHT absorption, *ASTROPHYSICS
Abstract: One of the key scientific objectives of the new generation high energy instruments is the quest for signatures from the extragalactic background light (EBL) at UV/optical/IR energies and its evolution by means of photon-photon absorption over extragalactic distances. I will discuss the various methods proposed, and biases that may be introduced when studying the evolution of the EBL with capable γ-ray observatories like e.g. GLAST or CTA, where the γ-ray horizon is probed by means of statistical analysis of absorption features in AGN spectra at various redshifts. In particular, the effect of the redshift-dependence of “local opacity” in γ-ray loud quasars due to possible γ-ray absorption through photon-photon pair production of jet photons in the external photon environments (accretion disk, broad-line region radiation field) on evolutionary studies of the EBL is highlighted. [ABSTRACT FROM AUTHOR]
Published: 2008
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7. Optimising Parameters for a multi-TeV IACT Cell.

Author: Denman, J., Rowell, G., Stamatescu, V., Thornton, G., Dunbar, R., Clay, R., Dawson, B., Smith, A., Wild, N., and Protheroe, R.
Subjects: *TELESCOPES, *ASTRONOMICAL instruments, *ASTRONOMY, *PHYSICAL sciences, *ASTROPHYSICS
Abstract: This report centres on a single cell of 5 telescopes which would be considered a pathfinder component for the full array. The investigation looks at the effects of image triggering conditions, telescope separation, image cleaning, image size and site altitude on the flux sensitivity, angular resolution and background rejection. This report presents preliminary results for individually varying these parameters. This provides the first guide in choosing the optimal configuration, where the emphasis is presently on the 10–100 TeV energy band. Results indicate that an improvement in q-factor and angular resolution is seen for telescope separation 200 m at E<10 TeV. The flux sensitivity achieved in the 10–100 TeV band is ∼2×10-12 ergs/cm2/s with an angular resolution of better than 0.1°. [ABSTRACT FROM AUTHOR]
Published: 2008
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8. A Source Identification Algorithm for INTEGRAL.

Author: Scaringi, Simone, Bird, Antony J., Clark, David J., Dean, Anthony J., Hill, Adam B., McBride, Vanessa A., and Shaw, Simon E.
Subjects: *ALGORITHMS, *MACHINE learning, *GAMMA rays, *TELESCOPES, *ASTROPHYSICS
Abstract: We give an overview of ISINA: INTEGRAL Source Identification Network Algorithm. This machine learning algorithm, using Random Forests, is applied to the IBIS/ISGRI dataset in order to ease the production of unbiased future soft gamma-ray source catalogues. The key steps of candidate searching, filtering and feature extraction are described. Three training and testing sets are created in order to deal with the diverse timescales and diverse objects encountered when dealing with the gamma-ray sky. Three independent Random Forest are built: one dealing with faint persistent source recognition, one dealing with strong persistent sources and a final one dealing with transients. For the latter, a new transient detection technique is introduced and described: the Transient Matrix. Finally the performance of the network is assessed and discussed using the testing set and some illustrative source examples. [ABSTRACT FROM AUTHOR]
Published: 2008
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9. Photo-nuclear Science using laser Compton scattering gamma-rays in JAEA.

Author: Hayakawa, Takehito and Hajima, Ryoichi
Subjects: *GAMMA rays, *SCATTERING (Physics), *NUCLEAR physics, *NUCLEAR astrophysics, *ASTROPHYSICS, *NUCLEAR energy, *RESONANCE, *FLUORESCENCE, *HEAVY metals, *RADIOACTIVE wastes, *RADIOACTIVE waste disposal
Abstract: The laser Compton scattering gamma-rays are a new generation of gamma-rays which have advantages of tunable energy, high energy resolution, and almost 100% polarization. These gamma-rays have been used for wide fields as nuclear physics, nuclear astrophysics, and atomic energy engineering. One of the most important topics is a management of nuclear waste. We have proposed a novel non-destructive assay method for isotopes using nuclear resonance fluorescence measurement with the Compton scattering gamma-rays. This assay system is useful for the nuclear waste management. We have successfully demonstrated the detection of a target isotope hidden in heavy metals. We used these gamma-rays for the study of the nuclear physics and nuclear astrophysics. We also have developed a new Compton scattering gamma-ray source with an energy region of sub-MeV. [ABSTRACT FROM AUTHOR]
Published: 2008
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10. Binaries and GLAST.

Author: Dubus, Guillaume
Subjects: *GAMMA ray bursts, *GAMMA ray astronomy, *IONIZING radiation, *INTERSTELLAR medium, *SPACE environment, *ASTROPHYSICS
Abstract: Radio and X-ray observations of the relativistic jets of microquasars show evidence for the acceleration of particles to very high energies. Signatures of non-thermal processes occurring closer in to the compact object can also be found. In addition, three binaries are now established emitters of high (>100 MeV) and/or very high (>100 GeV) energy gamma-rays. High-energy emission can originate from a microquasar jet (accretion-powered) or from a shocked pulsar wind (rotation-powered). I discuss the impact GLAST will have in the very near future on studies of such binaries. GLAST is expected to shed new light on the link between accretion and ejection in microquasars and to enable to probe pulsar winds on small scales in rotation-powered binaries. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]
Published: 2007
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11. THE AGILE MISSION AND GAMMA-RAY ASTROPHYSICS.

Author: TAVANI, MARCO
Subjects: GAMMA ray bursts, ASTROPHYSICS, ORBITING solar observatories, COSMIC rays, EXTRAGALACTIC distances
Published: 2002

12. A NICER look at the state transitions of the black hole candidate MAXI J1535-571 during its reflares

Author: M. Loewenstein, M. Armas Padilla, V. A. Cúneo, K. Alabarta, Mariano Mendez, Peter Bult, Jeroen Homan, A. C. Fabian, Keith C. Gendreau, James F. Steiner, T. Muñoz-Darias, Arkadip Basak, Francesco Tombesi, Jorge Ariel Combi, Diego Altamirano, Zaven Arzoumanian, R. Remillard, Joseph Neilsen, Abigail L. Stevens, D. J. K. Buisson, Liang Zhang, and Astronomy
Subjects: Astrophysics::High Energy Astrophysical Phenomena, black hole physics, X-ray binary, BINARIES [X-RAYS], FOS: Physical sciences, Binary number, purl.org/becyt/ford/1.7 [https], Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, BLACK HOLE PHYSICS, purl.org/becyt/ford/1 [https], GX 339-4, X-rays: binaries, accretion, accretion, accretion discs, stars: individual: MAXI J1535-571, Astrophysics::Solar and Stellar Astrophysics, NEUTRON-STAR, SAX J1808.4-3658, ACCRETION, Solar and Stellar Astrophysics (astro-ph.SR), INDIVIDUAL: MAXI J1535−571 [STARS], High Energy Astrophysical Phenomena (astro-ph.HE), Physics, LIGHT CURVES, TRANSIENT XTE-J1650-500, Neutron Star Interior Composition Explorer, Accretion (meteorology), X-RAY BINARY, Settore FIS/05, QUASI-PERIODIC OSCILLATIONS, Gamma ray, Astronomy and Astrophysics, Light curve, accretion discs, Black hole, Neutron star, GAMMA-RAY, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, DWARF-NOVA OUTBURSTS, Astrophysics - High Energy Astrophysical Phenomena, ACCRETION DISCS, ENHANCED MASS-TRANSFER
Abstract: The black hole candidate and X-ray binary MAXI J1535-571 was discovered in September 2017. During the decay of its discovery outburst, and before returning to quiescence, the source underwent at least four reflaring events, with peak luminosities of $\sim$10$^{35-36}$ erg s$^{-1}$ (d/4.1 kpc)$^2$. To investigate the nature of these flares, we analysed a sample of NICER observations taken with almost daily cadence. In this work we present the detailed spectral and timing analysis of the evolution of the four reflares. The higher sensitivity of NICER at lower energies, in comparison with other X-ray detectors, allowed us to constrain the disc component of the spectrum at $\sim$0.5 keV. We found that during each reflare the source appears to trace out a q-shaped track in the hardness-intensity diagram similar to those observed in black hole binaries during full outbursts. MAXI J1535-571 transits between the hard state (valleys) and softer states (peaks) during these flares. Moreover, the Comptonised component is undetected at the peak of the first reflare, while the disc component is undetected during the valleys. Assuming the most likely distance of 4.1 kpc, we find that the hard-to-soft transitions take place at the lowest luminosities ever observed in a black hole transient, while the soft-to-hard transitions occur at some of the lowest luminosities ever reported for such systems., Accepted for publication in MNRAS main journal
Published: 2020

13. Event Horizon Telescope imaging of the archetypal blazar 3C 279 at an extreme 20 microarcsecond resolution

Author: Robert Freund, N. W. Halverson, Benjamin R. Ryan, Paul Shaw, André Young, Andreas Eckart, A. Montaña, Michael Titus, Chen Yu Yu, Gertie Geertsema, Gao Feng, Ronald Grosslein, Ranjani Srinivasan, David Ball, Pablo Torne, Roberto Garcia, Hiroki Okino, Kotaro Moriyama, Chris Eckert, Lupin C.C. Lin, Geoffrey B. Crew, Vernon Fath, Freek Roelofs, David Sánchez-Arguelles, Luciano Rezzolla, Makoto Inoue, Michael Bremer, Jongsoo Kim, James Hoge, Michael Janssen, David M. Gale, Mel Rose, Jason Dexter, Do-Young Byun, J. G. A. Wouterloot, Rubén Herrero-Illana, Daniel C. M. Palumbo, Ta Shun Wei, Ching Tang Liu, Bradford Benson, Jadyn Anczarski, Patrick M. Koch, Ken Young, Jae-Young Kim, Minfeng Gu, Mislav Baloković, Mariafelicia De Laurentis, Laurent Loinard, A. Jiménez-Rosales, Tomohisa Kawashima, Nicolas Pradel, Heino Falcke, Olivier Gentaz, Dirk Muders, Shami Chatterjee, Britton Jeter, Rocco Lico, Craig Walther, David J. James, Homin Jiang, Michael H. Hecht, Gopal Narayanan, Qingwen Wu, Pierre Martin-Cocher, Michael A. Nowak, Alexander W. Raymond, Gregory Desvignes, Anne Kathrin Baczko, Chet Ruszczyk, Yutaka Hasegawa, Chao-Te Li, M. C. H. Wright, Andrew Nadolski, Alan P. Marscher, Christopher Beaudoin, Harriet Parsons, Peñalver Juan, Karl M. Menten, Silke Britzen, Frédéric Gueth, Shu Hao Chang, Andrew Chael, Daryl Haggard, Rodrigo Córdova Rosado, Ru-Sen Lu, Mansour Karami, José L. Gómez, Sang-Sung Lee, Tirupati K. Sridharan, Karl Friedrich Schuster, Ronald Hesper, Richard L. Plambeck, Iain Coulson, Jason SooHoo, Aristeidis Noutsos, Svetlana G. Jorstad, Li Ming Lu, James M. Cordes, David H. Hughes, Jonathan Weintroub, Chih-Wei Locutus Huang, Katherine L. Bouman, Roger J. Cappallo, Lijing Shao, Christiaan D. Brinkerink, John Kuroda, Ramesh Karuppusamy, Iniyan Natarajan, Jessica Dempsey, George Nystrom, John E. Carlstrom, Sera Markoff, Mark Kettenis, Neal R. Erickson, Jason W. Henning, R. Laing, Huang Lei, Kevin A. Dudevoir, Ilje Cho, William Stahm, Juan-Carlos Algaba, Junhan Kim, Hotaka Shiokawa, Martin P. McColl, James M. Moran, Chi-kwan Chan, Timothy C. Chuter, Thomas W. Folkers, Yi Chen, Christopher Greer, Lia Medeiros, C. Y. Kuo, Kuo Chang Han, Shoko Koyama, William Snow, Rurik A. Primiani, Sjoerd T. Timmer, F. Peter Schloerb, Stephen R. McWhirter, Fumie Tazaki, Norbert Wex, Ming-Tang Chen, Nimesh A. Patel, Aaron Faber, Mark Derome, Kazunori Akiyama, W. B. Everett, Hiroshi Nagai, Andrei Lobanov, Ignacio Ruiz, Pierre Christian, N. Phillips, David C. Forbes, Don Sousa, Michael Lindqvist, Christopher Risacher, Wen Ping Lo, Geoffrey C. Bower, Bart Ripperda, Dominique Broguiere, Maciek Wielgus, Antony A. Stark, Raquel Fraga-Encinas, Hiroaki Nishioka, Philippe Raffin, Hugo Messias, Feryal Özel, Jun Yi Koay, Buell T. Jannuzi, Sandra Bustamente, Roberto Neri, Jinchi Hao, Ye-Fei Yuan, Garrett K. Keating, Lynn D. Matthews, Avery E. Broderick, Mark G. Rawlings, Ciriaco Goddi, Tod R. Lauer, Kamal Souccar, Alan L. Roy, S. Navarro, Luis C. Ho, Timothy Norton, Roger Brissenden, Doosoo Yoon, Jongho Park, Richard Lacasse, Paul T. P. Ho, Derek Ward-Thompson, Atish Kamble, Akihiko Hirota, S. Sánchez, D. A. Graham, Vincent Piétu, Kyle D. Massingill, M. Zeballos, Mahito Sasada, Hideo Ogawa, Ziri Younsi, Chih Cheng Chang, Alejandro F. Sáez-Madain, Christian M. Fromm, Ramesh Narayan, Shuichiro Tsuda, Ryan Berthold, Gibwa Musoke, Laura Vertatschitsch, Masanori Nakamura, Remo P. J. Tilanus, Cornelia Müller, Kimihiro Kimura, Roman Gold, Venkatessh Ramakrishnan, Yuzhu Cui, Frederick K. Baganoff, Alan R. Whitney, Aleksandar Popstefanija, Helge Rottmann, Yuan Feng, Ralph Eatough, Tuomas Savolainen, Neil M. Nagar, Alexander Allardi, M. Mora-Klein, Thomas Bronzwaer, Mark Gurwell, Bong Won Sohn, Ivan Marti-Vidal, Chih Chiang Han, Hung Yi Pu, Yan-Rong Li, Shan Shan Zhao, Song Chu Chang, Zhi-Qiang Shen, John F. C. Wardle, Carsten Kramer, Koushik Chatterjee, Wagner Jan, Tomoaki Oyama, Ray Blundell, Motoki Kino, Alan E. E. Rogers, Rebecca Azulay, Jordy Davelaar, Tyler Trent, Satoki Matsushita, Kazi L.J. Rygl, Shuo Zhang, John E. Barrett, Peter Oshiro, Ryan Chilson, Jorge A. Preciado-López, Daniel Michalik, Peter Galison, Uwe Bach, Ilse van Bemmel, Pim Schellart, Michael D. Johnson, Jiang Wu, J. Anton Zensus, S. A. Dzib, Arturo I. Gómez-Ruiz, Meyer Zhao Zheng, David John, Dimitrios Psaltis, Daniel P. Marrone, M. Poirier, Shiro Ikeda, Ralph G. Marson, A. Hernandez-Gomez, Sven Dornbusch, George Reiland, Mareki Honma, J. Blanchard, Ed Fomalont, Taehyun Jung, Izumi Mizuno, Monika Moscibrodzka, Vincent L. Fish, Matthew R. Dexter, Paul Tiede, Rodrigo Amestica, Nicholas R. MacDonald, Gisela N. Ortiz-León, Colin J. Lonsdale, Callie Matulonis, Charles F. Gammie, Per Friberg, Boris Georgiev, W. Boland, Ramprasad Rao, Guang-Yao Zhao, Joseph R. Farah, Zhiyuan Li, Hector Olivares, Sara Issaoun, Elisabetta Liuzzo, C. M. Violette Impellizzeri, Michael Kramer, Oliver Porth, Thomas P. Krichbaum, Dominic W. Pesce, Daniel R. van Rossum, David R. Smith, Robert Wharton, Kuan Yu Liu, David P. Woody, Arash Roshanineshat, Sheperd S. Doeleman, Chung Chen Chen, Ziyan Zhu, Ue-Li Pen, Yosuke Mizuno, Prather Ben, Sascha Trippe, Walter Alef, Liu Kuo, Alexandra S. Rahlin, William Montgomerie, George N. Wong, Jirong Mao, Kazuhiro Hada, Efthalia Traianou, John Conway, Remi Sassella, Eduardo Ros, Kevin M. Silva, Derek Kubo, E. Castillo-Domínguez, Huib Jan van Langevelde, Keiichi Asada, Des Small, Joseph Neilsen, Chi H. Nguyen, Chunchong Ni, Yusuke Kono, Ryan Keisler, Paul Yamaguchi, Lindy Blackburn, Erik M. Leitch, Roger Deane, Lucy M. Ziurys, K. T. Story, Joseph Crowley, Nathan Whitehorn, Stefan Heyminck, Kenji Toma, Antxon Alberdi, Yau De Huang, Dan Bintley, Y Kim, J., Krichbaum, T. P., Broderick, A. E., Wielgus, M., Blackburn, L., Gomez, J. -L., Johnson, M. D., Bouman, K. L., Chael, A., Akiyama, K., Jorstad, S., Marscher, A. P., Issaoun, S., Janssen, M., Chan, C. -K., Savolainen, T., Pesce, D. W., Ozel, F., De Laurentis, M., Deane, R., Institut de RadioAstronomie Millimétrique (IRAM), Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Instituto de RadioAstronomía Milimétrica (IRAM), Event Horizon Telescope, Ministerio de Economía y Competitividad (España), European Commission, National Aeronautics and Space Administration (US), Max Planck Institute for Radio Astronomy, Perimeter Institute for Theoretical Physics, Harvard University, CSIC, Princeton University, Boston University, Radboud University Nijmegen, University of Arizona, Anne Lähteenmäki Group, Academia Sinica - Institute of Astronomy and Astrophysics, Massachusetts Institute of Technology, East Asian Observatory, Nederlandse Onderzoekschool voor Astronomie, Academia Sinica, Institut de Radio Astronomie Millimétrique, Korea Astronomy and Space Science Institute, University of Chicago, Cornell University, University of Amsterdam, CAS - Shanghai Astronomical Observatory, Chalmers University of Technology, National Astronomical Observatory of Japan, University of Naples Federico II, University of Pretoria, University of Colorado Boulder, National Radio Astronomy Observatory, Goethe University Frankfurt, University of Illinois at Urbana-Champaign, University of Waterloo, Instituto Nacional de Astrofisica Optica y Electronica, University of Groningen, Peking University, Max Planck Institute for Extraterrestrial Physics, Joint Institute for VLBI in Europe, California Institute of Technology, National Sun Yat-sen University, National Optical Astronomy Observatory, CAS - Institute of High Energy Physics, Nanjing University, INAF Istituto di Radioastronomia, Instituto de Radioastronomía y Astrofísica, CAS - National Astronomical Observatories, Universidad de Valencia, Universidad de Concepción, University of Massachusetts, Rhodes University, University of California Berkeley, Los Alamos National Laboratory, IRAM, Tohoku University, Seoul National University, Brandeis University, University of Central Lancashire, Huazhong University of Science and Technology, University of Science and Technology of China, University of Vermont, Villanova University, United States Department of Energy, Western University, Royal Netherlands Meteorological Institute, McGill University, Osaka Prefecture University, European Southern Observatory Santiago, University of Manchester, National Radio Astronomy Observatory Socorro, Rochester Institute of Technology, Washington University St. Louis, Systems and Technology Research, Georgia Institute of Technology, Stanford University, University of California Los Angeles, Department of Electronics and Nanoengineering, Aalto-yliopisto, Aalto University, Astronomy, High Energy Astrophys. & Astropart. Phys (API, FNWI), and Gravitation and Astroparticle Physics Amsterdam
Subjects: ACTIVE GALACTIC NUCLEI, Brightness, Active galactic nucleus, active [Galaxies], Astrophysics::High Energy Astrophysical Phenomena, Astronomy, galaxies: active, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Submillimeter Array, FLOWS, SCALE CIRCULAR-POLARIZATION, 0103 physical sciences, Very-long-baseline interferometry, Blazar, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, Event Horizon Telescope, [PHYS]Physics [physics], Jet (fluid), 010308 nuclear & particles physics, Astronomy and Astrophysics, FLARE, galaxies: jets, individual: 3C 279 [Galaxies], LONG, VARIABILITY, galaxies: individual: 3C 279, GAMMA-RAY, QUASARS, 13. Climate action, Space and Planetary Science, techniques: interferometric, Brightness temperature, ACCRETION DISKS, interferometric [Techniques], jets [Galaxies], RELATIVISTIC JETS, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Open Access funding provided by Max Planck Society.--All authors: Kim, Jae-Young; Krichbaum, Thomas P.; Broderick, Avery E.; Wielgus, Maciek; Blackburn, Lindy; Gómez, José L.; Johnson, Michael D.; Bouman, Katherine L.; Chael, Andrew; Akiyama, Kazunori; Jorstad, Svetlana; Marscher, Alan P.; Issaoun, Sara; Janssen, Michael; Chan, Chi-kwan; Savolainen, Tuomas; Pesce, Dominic W.; Özel, Feryal; Alberdi, Antxon; Alef, Walter Asada, Keiichi; Azulay, Rebecca; Baczko, Anne-Kathrin; Ball, David; Baloković, Mislav; Barrett, John; Bintley, Dan; Boland, Wilfred; Bower, Geoffrey C.; Bremer, Michael; Brinkerink, Christiaan D.; Brissenden, Roger; Britzen, Silke; Broguiere, Dominique; Bronzwaer, Thomas; Byun, Do-Young; Carlstrom, John E.; Chatterjee, Shami; Chatterjee, Koushik; Chen, Ming-Tang; Chen, Yongjun; Cho, Ilje; Christian, Pierre; Conway, John E.; Cordes, James M.; Crew, Geoffrey B.; Cui, Yuzhu; Davelaar, Jordy; De Laurentis, Mariafelicia; Deane, Roger; Dempsey, Jessica; Desvignes, Gregory; Dexter, Jason; Doeleman, Sheperd S.; Eatough, Ralph P.; Falcke, Heino; Fish, Vincent L.; Fomalont, Ed; Fraga-Encinas, Raquel; Friberg, Per; Fromm, Christian M.; Galison, Peter; Gammie, Charles F.; García, Roberto; Gentaz, Olivier; Georgiev, Boris; Goddi, Ciriaco; Gold, Roman; Gómez-Ruiz, Arturo I.; Gu, Minfeng; Gurwell, Mark; Hada, Kazuhiro; Hecht, Michael H.; Hesper, Ronald; Ho, Luis C.; Ho, Paul; Honma, Mareki; Huang, Chih-Wei L.; Huang, Lei; Hughes, David H.; Ikeda, Shiro; Inoue, Makoto; James, David J.; Jannuzi, Buell T.; Jeter, Britton; Jiang, Wu; Jimenez-Rosales, Alejandra; Jung, Taehyun; Karami, Mansour; Karuppusamy, Ramesh; Kawashima, Tomohisa; Keating, Garrett K.; Kettenis, Mark; Kim, Junhan; Kim, Jongsoo; Kino, Motoki; Koay, Jun Yi; Koch, Patrick M.; Koyama, Shoko; Kramer, Michael; Kramer, Carsten; Kuo, Cheng-Yu; Lauer, Tod R.; Lee, Sang-Sung; Li, Yan-Rong; Li, Zhiyuan; Lindqvist, Michael; Lico, Rocco; Liu, Kuo; Liuzzo, Elisabetta; Lo, Wen-Ping; Lobanov, Andrei P.; Loinard, Laurent; Lonsdale, Colin; Lu, Ru-Sen; MacDonald, Nicholas R.; Mao, Jirong; Markoff, Sera; Marrone, Daniel P.; Martí-Vidal, Iván; Matsushita, Satoki; Matthews, Lynn D.; Medeiros, Lia; Menten, Karl M.; Mizuno, Yosuke; Mizuno, Izumi; Moran, James M.; Moriyama, Kotaro; Moscibrodzka, Monika; Musoke, Gibwa; Müller, Cornelia; Nagai, Hiroshi; Nagar, Neil M.; Nakamura, Masanori; Narayan, Ramesh; Narayanan, Gopal; Natarajan, Iniyan; Neri, Roberto; Ni, Chunchong; Noutsos, Aristeidis; Okino, Hiroki; Olivares, Héctor; Ortiz-León, Gisela N.; Oyama, Tomoaki; Palumbo, Daniel C. M.; Park, Jongho; Patel, Nimesh; Pen, Ue-Li; Piétu, Vincent; Plambeck, Richard; PopStefanija, Aleksandar; Porth, Oliver; Prather, Ben; Preciado-López, Jorge A.; Psaltis, Dimitrios; Pu, Hung-Yi; Ramakrishnan, Venkatessh; Rao, Ramprasad; Rawlings, Mark G.; Raymond, Alexander W.; Rezzolla, Luciano; Ripperda, Bart; Roelofs, Freek; Rogers, Alan; Ros, Eduardo; Rose, Mel; Roshanineshat, Arash; Rottmann, Helge; Roy, Alan L.; Ruszczyk, Chet; Ryan, Benjamin R.; Rygl, Kazi L. J.; Sánchez, Salvador; Sánchez-Arguelles, David; Sasada, Mahito; Schloerb, F. Peter; Schuster, Karl-Friedrich; Shao, Lijing; Shen, Zhiqiang; Small, Des; Sohn, Bong Won; SooHoo, Jason; Tazaki, Fumie; Tiede, Paul; Tilanus, Remo P. J.; Titus, Michael; Toma, Kenji; Torne, Pablo; Trent, Tyler; Traianou, Efthalia; Trippe, Sascha; Tsuda, Shuichiro; van Bemmel, Ilse; van Langevelde, Huib Jan; van Rossum, Daniel R.; Wagner, Jan; Wardle, John; Ward-Thompson, Derek; Weintroub, Jonathan; Wex, Norbert; Wharton, Robert; Wong, George N.; Wu, Qingwen; Yoon, Doosoo; Young, André; Young, Ken; Younsi, Ziri; Yuan, Feng; Yuan, Ye-Fei; Zensus, J. Anton; Zhao, Guangyao; Zhao, Shan-Shan; Zhu, Ziyan; Algaba, Juan-Carlos; Allardi, Alexander; Amestica, Rodrigo; Anczarski, Jadyn; Bach, Uwe; Baganoff, Frederick K.; Beaudoin, Christopher; Benson, Bradford A.; Berthold, Ryan; Blanchard, Jay M.; Blundell, Ray; Bustamente, Sandra; Cappallo, Roger; Castillo-Domínguez, Edgar; Chang, Chih-Cheng; Chang, Shu-Hao; Chang, Song-Chu; Chen, Chung-Chen; Chilson, Ryan; Chuter, Tim C.; Rosado, Rodrigo Córdova; Coulson, Iain M.; Crowley, Joseph; Derome, Mark; Dexter, Matthew; Dornbusch, Sven; Dudevoir, Kevin A.; Dzib, Sergio A.; Eckart, Andreas; Eckert, Chris; Erickson, Neal R.; Everett, Wendeline B.; Faber, Aaron; Farah, Joseph R.; Fath, Vernon; Folkers, Thomas W.; Forbes, David C.; Freund, Robert; Gale, David M.; Gao, Feng; Geertsema, Gertie; Graham, David A.; Greer, Christopher H.; Grosslein, Ronald; Gueth, Frédéric; Haggard, Daryl; Halverson, Nils W.; Han, Chih-Chiang; Han, Kuo-Chang; Hao, Jinchi; Hasegawa, Yutaka; Henning, Jason W.; Hernández-Gómez, Antonio; Herrero-Illana, Rubén; Heyminck, Stefan; Hirota, Akihiko; Hoge, James; Huang, Yau-De; Violette Impellizzeri, C. M.; Jiang, Homin; John, David; Kamble, Atish; Keisler, Ryan; Kimura, Kimihiro; Kono, Yusuke; Kubo, Derek; Kuroda, John; Lacasse, Richard; Laing, Robert A.; Leitch, Erik M.; Li, Chao-Te; Lin, Lupin C. -C.; Liu, Ching-Tang; Liu, Kuan-Yu; Lu, Li-Ming; Marson, Ralph G.; Martin-Cocher, Pierre L.; Massingill, Kyle D.; Matulonis, Callie; McColl, Martin P.; McWhirter, Stephen R.; Messias, Hugo; Meyer-Zhao, Zheng; Michalik, Daniel; Montaña, Alfredo; Montgomerie, William; Mora-Klein, Matias; Muders, Dirk; Nadolski, Andrew; Navarro, Santiago; Neilsen, Joseph; Nguyen, Chi H.; Nishioka, Hiroaki; Norton, Timothy; Nowak, Michael A.; Nystrom, George; Ogawa, Hideo; Oshiro, Peter; Oyama, Tomoaki; Parsons, Harriet; Peñalver, Juan; Phillips, Neil M.; Poirier, Michael; Pradel, Nicolas; Primiani, Rurik A.; Raffin, Philippe A.; Rahlin, Alexandra S.; Reiland, George; Risacher, Christopher; Ruiz, Ignacio; Sáez-Madaín, Alejandro F.; Sassella, Remi; Schellart, Pim; Shaw, Paul; Silva, Kevin M.; Shiokawa, Hotaka; Smith, David R.; Snow, William; Souccar, Kamal; Sousa, Don; Sridharan, Tirupati K.; Srinivasan, Ranjani; Stahm, William; Stark, Antony A.; Story, Kyle; Timmer, Sjoerd T.; Vertatschitsch, Laura; Walther, Craig; Wei, Ta-Shun; Whitehorn, Nathan; Whitney, Alan R.; Woody, David P.; Wouterloot, Jan G. A.; Wright, Melvin; Yamaguchi, Paul; Yu, Chen-Yu; Zeballos, Milagros; Zhang, Shuo; Ziurys, Lucy; Event Horizon Telescope Collaboration, 3C 279 is an archetypal blazar with a prominent radio jet that show broadband flux density variability across the entire electromagnetic spectrum. We use an ultra-high angular resolution technique - global Very Long Baseline Interferometry (VLBI) at 1.3mm (230 GHz) - to resolve the innermost jet of 3C 279 in order to study its fine-scale morphology close to the jet base where highly variable-ray emission is thought to originate, according to various models. The source was observed during four days in April 2017 with the Event Horizon Telescope at 230 GHz, including the phased Atacama Large Millimeter/submillimeter Array, at an angular resolution of ∼20 μas (at a redshift of z = 0:536 this corresponds to ∼0:13 pc ∼ 1700 Schwarzschild radii with a black hole mass MBH = 8 × 108 M⊙). Imaging and model-fitting techniques were applied to the data to parameterize the fine-scale source structure and its variation.We find a multicomponent inner jet morphology with the northernmost component elongated perpendicular to the direction of the jet, as imaged at longer wavelengths. The elongated nuclear structure is consistent on all four observing days and across diffierent imaging methods and model-fitting techniques, and therefore appears robust. Owing to its compactness and brightness, we associate the northern nuclear structure as the VLBI "core". This morphology can be interpreted as either a broad resolved jet base or a spatially bent jet.We also find significant day-to-day variations in the closure phases, which appear most pronounced on the triangles with the longest baselines. Our analysis shows that this variation is related to a systematic change of the source structure. Two inner jet components move non-radially at apparent speeds of ∼15 c and ∼20 c (∼1:3 and ∼1:7 μas day-1, respectively), which more strongly supports the scenario of traveling shocks or instabilities in a bent, possibly rotating jet. The observed apparent speeds are also coincident with the 3C 279 large-scale jet kinematics observed at longer (cm) wavelengths, suggesting no significant jet acceleration between the 1.3mm core and the outer jet. The intrinsic brightness temperature of the jet components are ≤1010 K, a magnitude or more lower than typical values seen at ≥7mm wavelengths. The low brightness temperature and morphological complexity suggest that the core region of 3C 279 becomes optically thin at short (mm) wavelengths. © J.-Y. Kim et al. 2020., The authors of the present paper thank the following organizations and programs: the Academy of Finland (projects 274477, 284495, 312496); the Advanced European Network of E-infrastructures for Astronomy with the SKA (AENEAS) project, supported by the European Commission Framework Programme Horizon 2020 Research and Innovation action under grant agreement 731016; the Alexander von Humboldt Stiftung; the Black Hole Initiative at Harvard University, through a grant (60477) from the John Templeton Foundation; the China Scholarship Council; Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT, Chile, via PIA ACT172033, Fondecyt projects 1171506 and 3190878, BASAL AFB-170002, ALMA-conicyt 31140007); Consejo Nacional de Ciencia y Tecnologia (CONACYT, Mexico, projects 104497, 275201, 279006, 281692); the Delaney Family via the Delaney Family John A. Wheeler Chair at Perimeter Institute; Direccion General de Asuntos del Personal Academico -Universidad Nacional Autonoma de Mexico (DGAPA -UNAM, project IN112417); the European Research Council Synergy Grant "BlackHoleCam: Imaging the Event Horizon of Black Holes" (grant 610058); the Generalitat Valenciana postdoctoral grant APOSTD/2018/177 and GenT Program (project CIDEGENT/2018/021); the Gordon and Betty Moore Foundation (grants GBMF-3561, GBMF-5278); the Istituto Nazionale di Fisica Nucleare (INFN) sezione di Napoli, iniziative specifiche TEONGRAV; the International Max Planck Research School for Astronomy and Astrophysics at the Universities of Bonn and Cologne; the Jansky Fellowship program of the National Radio Astronomy Observatory (NRAO); the Japanese Government (Monbukagakusho: MEXT) Scholarship; the Japan Society for the Promotion of Science (JSPS) Grant-inAid for JSPS Research Fellowship (JP17J08829); the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (CAS, grants QYZDJSSW-SLH057, QYZDJ-SSW-SYS008, ZDBS-LY-SLH011); the Leverhulme Trust Early Career Research Fellowship; the Malaysian Fundamental Research Grant Scheme (FRGS, grant FRGS/1/2019/STG02/UM/02/6); the Max-PlanckGesellschaft (MPG); the Max Planck Partner Group of the MPG and the CAS; the MEXT/JSPS KAKENHI (grants 18KK0090, JP18K13594, JP18K03656, JP18H03721, 18K03709, 18H01245, 25120007); the MIT International Science and Technology Initiatives (MISTI) Funds; the Ministry of Science and Technology (MOST) of Taiwan (105-2112-M-001-025-MY3, 106-2112-M-001-011, 106-2119-M-001-027, 107-2119-M-001-017, 107-2119-M-001-020, and 107-2119-M-110-005); the National Aeronautics and Space Administration (NASA, Fermi Guest Investigator grant 80NSSC17K0649 and Hubble Fellowship grant HST-HF2-51431.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc. r , for NASA, under contract NAS5-26555); the National Institute of Natural Sciences (NINS) of Japan; the National Key Research and Development Program of China (grant 2016YFA0400704, 2016YFA0400702); the National Science Foundation (NSF, grants AST-0096454, AST-0352953, AST-0521233, AST-0705062, AST-0905844, AST-0922984, AST-1126433, AST-1140030, DGE-1144085, AST-1207704, AST-1207730, AST-1207752, MRI-1228509, OPP-1248097, AST-1310896, AST-1312651, AST-1337663, AST-1440254, AST-1555365, AST-1715061, AST-1615796, AST-1716327, OISE-1743747, AST-1816420); the Natural Science Foundation of China (grants 11573051, 11633006, 11650110427, 10625314, 11721303, 11725312, 11933007); the Natural Sciences and Engineering Research Council of Canada (NSERC, including a Discovery Grant and the NSERC Alexander Graham Bell Canada Graduate Scholarships-Doctoral Program); the National Youth Thousand Talents Program of China; the National Research Foundation of Korea (the Global PhD Fellowship Grant: grants NRF-2015H1A2A1033752, 2015-R1D1A1A01056807, the Korea Research Fellowship Program: NRF-2015H1D3A1066561); the Netherlands Organization for Scientific Research (NWO) VICI award (grant 639.043.513) and Spinoza Prize SPI 78-409; the New Scientific Frontiers with Precision Radio Interferometry Fellowship awarded by the South African Radio Astronomy Observatory (SARAO), which is a facility of the National Research Foundation (NRF), an agency of the Department of Science and Technology (DST) of South Africa; the Onsala Space Observatory (OSO) national infrastructure, for the provisioning of its facilities/observational support (OSO receives funding through the Swedish Research Council under grant 2017-00648) the Perimeter Institute for Theoretical Physics (research at Perimeter Institute is supported by the Government of Canada through the Department of Innovation, Science and Economic Development and by the Province of Ontario through the Ministry of Research, Innovation and Science); the Russian Science Foundation (grant 17-12-01029); the Spanish Ministerio de Economia y Competitividad (grants PGC2018-098915-B-C21, AYA201680889-P); the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award for the Instituto de Astrofisica de Andalucia (SEV-2017-0709); the Toray Science Foundation; the US Department of Energy (USDOE) through the Los Alamos National Laboratory (operated by Triad National Security, LLC, for the National Nuclear Security Administration of the USDOE (Contract 89233218CNA000001)); the Italian Ministero dell'Istruzione Universita e Ricerca through the grant Progetti Premiali 2012-iALMA (CUP C52I13000140001); the European Union's Horizon 2020 research and innovation programme under grant agreement No 730562 RadioNet; ALMA North America Development Fund; the Academia Sinica; Chandra TM6-17006X; the GenT Program (Generalitat Valenciana) Project CIDEGENT/2018/021. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), supported by NSF grant ACI-1548562, and CyVerse, supported by NSF grants DBI-0735191, DBI-1265383, and DBI1743442. XSEDE Stampede2 resource at TACC was allocated through TGAST170024 and TG-AST080026N. XSEDE JetStream resource at PTI and TACC was allocated through AST170028. The simulations were performed in part on the SuperMUC cluster at the LRZ in Garching, on the LOEWE cluster in CSC in Frankfurt, and on the HazelHen cluster at the HLRS in Stuttgart. This research was enabled in part by support provided by Compute Ontario (http://computeontario. r ca), Calcul Quebec (http://www.calculquebec.ca) and Compute Canada (http://www.computecanada.ca).We thank the sta ff at the participating observatories, correlation centers, and institutions for their enthusiastic support. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2016.1.01154.V, ADS/JAO.ALMA#2016.1.01176.V. ALMA is a partnership of the European Southern Observatory (ESO; Europe, representing its member states), NSF, and National Institutes of Natural Sciences of Japan, together with National Research Council (Canada), Ministry of Science and Technology (MOST; Taiwan), Academia Sinica Institute of Astronomy and Astrophysics (ASIAA; Taiwan), and Korea Astronomy and Space Science Institute (KASI; Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, Associated Universities, Inc. (AUI)/NRAO, and the National Astronomical Observatory of Japan (NAOJ). The NRAO is a facility of the NSF operated under cooperative agreement by AUI. APEX is a collaboration between the Max-Planck-Institut fur Radioastronomie (Germany), ESO, and the Onsala Space Observatory (Sweden). The SMA is a joint project between the SAO and ASIAA and is funded by the Smithsonian Institution and the Academia Sinica. The JCMT is operated by the East Asian Observatory on behalf of the NAOJ, ASIAA, and KASI, as well as the Ministry of Finance of China, Chinese Academy of Sciences, and the National Key R&D Program (No. 2017YFA0402700) of China. Additional funding support for the JCMT is provided by the Science and Technologies Facility Council (UK) and participating universities in the UK and Canada. The LMT is a project operated by the Instituto Nacional de Astrofisica, Optica, y Electronica (Mexico) and the University of Massachusetts at Amherst (USA). The IRAM 30-m telescope on Pico Veleta, Spain is operated by IRAM and supported by CNRS (Centre National de la Recherche Scientifique, France), MPG (Max-Planck-Gesellschaft, Germany) and IGN (Instituto Geografico Nacional, Spain). The SMT is operated by the Arizona Radio Observatory, a part of the Steward Observatory of the University of Arizona, with financial support of operations from the State of Arizona and financial support for instrumentation development from the NSF. The SPT is supported by the National Science Foundation through grant PLR1248097. Partial support is also provided by the NSF Physics Frontier Center grant PHY-1125897 to the Kavli Institute of Cosmological Physics at the University of Chicago, the Kavli Foundation and the Gordon and Betty Moore Foundation grant GBMF 947. The SPT hydrogen maser was provided on loan from the GLT, courtesy of ASIAA. The EHTC has received generous donations of FPGA chips from Xilinx Inc., under the Xilinx University Program. The EHTC has benefited from technology shared under open-source license by the Collaboration for Astronomy Signal Processing and Electronics Research (CASPER). The EHT project is grateful to T4Science and Microsemi for their assistance with Hydrogen Masers. This research has made use of NASA's Astrophysics Data System. We gratefully acknowledge the support provided by the extended sta ff of the ALMA, both from the inception of the ALMA Phasing Project through the observational campaigns of 2017 and 2018. We would like to thank A. Deller and W. Brisken for EHT-specific support with the use of DiFX. We acknowledge the significance that Maunakea, where the SMA and JCMT EHT stations are located, has for the indigenous Hawaiian people. r This research has made use of data obtained with the Global Millimeter VLBI Array (GMVA), which consists of telescopes operated by the MPIfR, IRAM, Onsala, Metsahovi, Yebes, the Korean VLBI Network, the Green Bank Observatory and the Very Long Baseline Array (VLBA). The VLBA is an instrument of the National Radio Astronomy Observatory. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated by Associated Universities, Inc. The data were correlated at the correlator of the MPIfR in Bonn, Germany. This study makes use of 43 GHz VLBA data from the VLBA-BU Blazar Monitoring Program (VLBABU-BLAZAR; http://www.bu.edu/blazars/VLBAproject.html), funded by NASA through the Fermi Guest Investigator Program.
Published: 2020

14. International workshop on next generation gamma-ray source

Author: Ying Wu, Haiyan Gao, Anton Tonchev, Norbert Pietralla, Mike Kovash, Matthias Schindler, Fabian Zomer, J. R. M. Annand, Chuanxiang Tang, Jun Yan, M. H. Sikora, Daniel R. Phillips, Gerald Feldman, R. V. F. Janssens, David E. Davis, V. Werner, Hao Hao, S. Chattopadhyay, Carl R. Brune, J. Matthew Durham, C. M. Sun, Werner Tornow, Ani Aprahamian, Rory Miskimen, E. J. Downie, H. R. Weller, Zheng Zhao, Arthur E Champagne, Dimiter Balabanski, D. Hornidge, C. A. Ur, Phillip Martel, J M Byrd, Cameron Geddes, Andrei Afanasev, Harald W. Griesshammer, Deniz Savran, Johann Isaak, Andreas Zilges, Ryoichi Hajima, C. R. Howell, Aron M. Bernstein, David Alesini, Brian C. Tiburzi, Roxanne P. Springer, Barbara Pasquini, Mohammad Ahmed, Bruce E. Carlsten, Stephen V. Benson, Ulf-G. Meissner, David Kendellen, W. Michael Snow, Dong Wang, Laboratoire de l'Accélérateur Linéaire (LAL), and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)
Subjects: Accelerator Physics (physics.acc-ph), Nuclear and High Energy Physics, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Nuclear Theory, nucleon: structure, pi: photoproduction, [PHYS.PHYS.PHYS-ACC-PH]Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph], conference summary, nuclear astrophysics, FOS: Physical sciences, low-energy QCD, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], bremsstrahlung, 01 natural sciences, electron: accelerator, Nuclear Theory (nucl-th), parity: violation, nuclear physics, quantum chromodynamics, 0103 physical sciences, Agency (sociology), ddc:530, gamma-ray, Applied research, Nuclear Experiment (nucl-ex), 010306 general physics, photon: beam, Nuclear Experiment, activity report, energy: low, Physics, astrophysics, 010308 nuclear & particles physics, Information sharing, laser, hadronic parity violation, gamma ray, nuclear structure, Systems engineering, Physics - Accelerator Physics, Compton scattering
Abstract: Journal of physics / G 49(1), 010502 (2022). doi:10.1088/1361-6471/ac2827, Published by IOP Publ., Bristol
Published: 2021

15. A Trigger Interface Board for the Large and Medium Sized telescopes of the Cherenkov Telescope Array.

Author: Tejedor, Luis A., Barrio, Juan A., Peñil, Pablo, Pérez, Alejandro, Herranz, Diego, and Martín, Jorge
Subjects: *COMPUTER firmware, *TCP/IP, *TELESCOPES, *PERSONAL computers, *CAMERAS
Abstract: This paper presents the Trigger Interface Board (TIB), a system in charge of managing the trigger and clock signals in the cameras for the Large- and Medium-Sized telescopes in the Cherenkov Telescope Array (CTA). The TIB includes interfaces with the neighboring telescopes and with other subsystems in the camera. It receives trigger pulses from different origins and decides when those trigger signals should cause the camera readout. The decision is based on slow control parameters, the TIB internal state, the busy state of the camera, and the coincidence in time with other telescopes in a hardware stereo trigger scheme. Depending on the trigger origin, the TIB also generates an event data fragment, that is delivered to the camera Event Builder as part of the full raw event data. Additionally, it provides camera data-taking information to CTA central instances for monitoring purposes. The design of the TIB is based on two main components, namely an FPGA and a microcomputer. This structure provides fast digital processing capabilities, high-level software features for slow control and TCP/IP communication, and, especially, great flexibility to develop functionalities by working on the firmware and software levels separately. [ABSTRACT FROM AUTHOR]
Published: 2022
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16. Development of a quasi-monoenergetic 6MeV Gamma Facility at NASA Goddard Space Flight Center

Author: Nowicki, Suzanne F., Hunter, Stanley D., and Parsons, Ann M.
Subjects: *GAMMA rays, *METAL detectors, *NEUTRON capture, *ASTROPHYSICS
Abstract: Abstract: The 6MeV Gamma Facility has been developed at NASA Goddard Space Flight Center (GSFC) to allow in-house characterization and testing of a wide range of gamma-ray instruments such as pixelated CdZnTe detectors for planetary science and Compton and pair-production imaging telescopes for astrophysics. The 6MeV Gamma Facility utilizes a circulating flow of water irradiated by 14MeV neutrons to produce gamma rays via neutron capture on oxygen (16O(n,p)16N→16O⁎→16O+γ). The facility provides a low cost, in-house source of 2.742, 6.129 and 7.117MeV gamma rays, near the lower energy range of most accelerators and well above the 2.614 MeV line from the 228Th decay chain, the highest energy gamma ray available from a natural radionuclide. The 7.13s half-life of the 16N decay allows the water to be irradiated on one side of a large granite block and pumped to the opposite side to decay. Separating the irradiation and decay regions allows for shielding material, the granite block, to be placed between them, thus reducing the low-energy gamma-ray continuum. Comparison between high purity germanium (HPGe) spectra from the facility and a manufactured source, 238Pu/13C, shows that the low-energy continuum from the facility is reduced by a factor ∼30 and the gamma-ray rate is ∼100 times higher at 6.129MeV. [Copyright &y& Elsevier]
Published: 2013
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17. Fermi large area telescope highlights

Author: Morselli, Aldo
Subjects: *GAMMA ray telescopes, *ASTRONOMICAL observations, *GAMMA ray astronomy, *NUCLEAR energy, *PARTICLES (Nuclear physics), *ASTROPHYSICS
Abstract: Abstract: Successfully launched in June 2008, the Fermi Gamma-ray Space Telescope, formerly named GLAST, has been observing the high-energy gamma-ray sky with unprecedented sensitivity in the 20MeV–300GeV energy range and electrons + positrons in the 7GeV–1TeV range, opening a new observational window on a wide variety of astrophysical objects. [Copyright &y& Elsevier]
Published: 2012
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18. Probing the nature of short swift bursts via deep INTEGRAL monitoring of GRB 050925

Author: Sakamoto, T., Barbier, L., Barthelmy, S.D., Cummings, J.R., Fenimore, E.E., Gehrels, N., Krimm, H.A., Markwardt, C.B., Palmer, D.M., Parsons, A.M., Sato, G., Stamatikos, M., and Tueller, J.
Subjects: *GAMMA ray bursts, *X-ray bursts, *ASTRONOMICAL observatories, *ASTRONOMICAL observations, *ASTROPHYSICS, *X-ray astronomy, *GALACTIC X-ray sources
Abstract: Abstract: We present results from Swift, XMM-Newton, and deep INTEGRAL monitoring in the region of GRB 050925. This short Swift burst is a candidate for a newly discovered soft gamma-ray repeater (SGR) with the following observational burst properties: (1) galactic plane (b =−0.1°) localization, (2) 150ms duration, and (3) a blackbody rather than a simple power-law spectral shape (with a significance level of 97%). We found two possible X-ray counterparts of GRB 050925 by comparing the X-ray images from Swift XRT and XMM-Newton. Both X-ray sources show the transient behavior with a power-law decay index shallower than −1. We found no hard X-ray emission nor any additional burst from the location of GRB 050925 in ∼5ms of INTEGRAL data. We discuss about the three BATSE short bursts which might be associated with GRB 050925, based on their location and the duration. Assuming GRB 050925 is associated with the HII regions (W 58) at the galactic longitude of l =70°, we also discuss the source frame properties of GRB 050925. [Copyright &y& Elsevier]
Published: 2011
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19. The on-orbit calibration of the Fermi Large Area Telescope

Author: Abdo, A.A., Ackermann, M., Ajello, M., Ampe, J., Anderson, B., Atwood, W.B., Axelsson, M., Bagagli, R., Baldini, L., Ballet, J., Barbiellini, G., Bartelt, J., Bastieri, D., Baughman, B.M., Bechtol, K., Bédérède, D., Bellardi, F., Bellazzini, R., Belli, F., and Berenji, B.
Subjects: *CALIBRATION, *TELESCOPES, *ASTROPHYSICS, *SPACE vehicles, *LITERATURE publishing, *MATHEMATICAL optimization, *GALACTIC cosmic rays
Abstract: Abstract: The Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope began its on-orbit operations on June 23, 2008. Calibrations, defined in a generic sense, correspond to synchronization of trigger signals, optimization of delays for latching data, determination of detector thresholds, gains and responses, evaluation of the perimeter of the South Atlantic Anomaly (SAA), measurements of live time, of absolute time, and internal and spacecraft boresight alignments. Here we describe on-orbit calibration results obtained using known astrophysical sources, galactic cosmic rays, and charge injection into the front-end electronics of each detector. Instrument response functions will be described in a separate publication. This paper demonstrates the stability of calibrations and describes minor changes observed since launch. These results have been used to calibrate the LAT datasets to be publicly released in August 2009. [Copyright &y& Elsevier]
Published: 2009
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20. The Burst Alert Telescope (BAT) on the SWIFT Midex Mission.

Author: Barthelmy, Scott, Barbier, Louis, Cummings, Jay, Fenimore, Ed, Gehrels, Neil, Hullinger, Derek, Krimm, Hans, Markwardt, Craig, Palmer, David, Parsons, Ann, Sato, Goro, Suzuki, Masaya, Takahashi, Tadayuki, Tashiro, Makota, and Tueller, Jack
Subjects: *TELESCOPES, *OPTICAL instruments, *SPACE vehicles, *GAMMA ray bursts, *ASTROPHYSICS, *AFTERGLOW (Physics)
Abstract: he burst alert telescope (BAT) is one of three instruments on the Swift MIDEX spacecraft to study gamma-ray bursts (GRBs). The BAT first detects the GRB and localizes the burst direction to an accuracy of 1–4 arcmin within 20 s after the start of the event. The GRB trigger initiates an autonomous spacecraft slew to point the two narrow field-of-view (FOV) instruments at the burst location within 20–70 s so to make follow-up X-ray and optical observations. The BAT is a wide-FOV, coded-aperture instrument with a CdZnTe detector plane. The detector plane is composed of 32,768 pieces of CdZnTe (4×4×2 mm), and the coded-aperture mask is composed of ∼52,000 pieces of lead (5×5×1 mm) with a 1-m separation between mask and detector plane. The BAT operates over the 15–150 keV energy range with ∼7 keV resolution, a sensitivity of ∼10−8 erg s−1 cm−2, and a 1.4 sr (half-coded) FOV. We expect to detect > 100 GRBs/year for a 2-year mission. The BAT also performs an all-sky hard X-ray survey with a sensitivity of ∼2 m Crab (systematic limit) and it serves as a hard X-ray transient monitor. [ABSTRACT FROM AUTHOR]
Published: 2005
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21. IBIS detector performance during calibration — preliminary analysis

Author: Bazzano, A., Bird, A.J., Laurent, P., Malaguti, G., Quadrini, E.M., Segreto, A., Volkmer, R., Del Santo, M., Gabriele, M., and Tikkanen, T.
Subjects: *TELESCOPES, *CELESTIAL mechanics, *ASTROPHYSICS
Abstract: The IBIS telescope is a high angular resolution gamma-ray imager due to be launched on the INTEGRAL satellite on October 17, 2002. The scientific goal of IBIS is to study astrophysical processes from celestial sources and diffuse regions in the hard X-ray and soft gamma-ray domains. IBIS features a coded aperture imaging system and a novel large area (∼3000 cm2) multilayer pixellated detector which utilises both cadmium telluride (16,384 detectors) and caesium iodide elements (4096 detectors) surrounded by a BGO active veto shield. We present an overview of, and preliminary analysis from, the IBIS calibration campaign. The performance of each pixel has been characterised, and hence the scientific performance of the IBIS detector system as a whole can now be established. [Copyright &y& Elsevier]
Published: 2003
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22. Gamma-ray polarimetry

Author: Tajima, Hiroyasu
Subjects: *ASTROPHYSICS, *SILICON, *DETECTORS, *SEMICONDUCTORS
Abstract: An astrophysics application of a low-noise Double-sided Silicon Strip Detector (DSSD) is described. A Semiconductor Multiple-Compton Telescope (SMCT) is being developed to explore the γ-ray universe in the 0.1–20 MeV energy range. Excellent energy resolution and polarization sensitivity are key features of the SMCT. We have developed prototype modules for a low-noise DSSD system that achieved an energy resolution of 1.3 keV (FWHM) for 122 keV at 0°C. Results of a gamma-ray imaging test are also presented. [Copyright &y& Elsevier]
Published: 2003
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23. Cosmological evolution of quasar radio emission in the view of multifractality

Author: Joni Tammi, Merja Tornikosk, I. C. Leão, B. L. Canto Martins, A. Bewketu Belete, J. R. De Medeiros, Anne Lähteenmäki, Smain Femmam, Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA)), Universidade Federal do Rio Grande do Norte, Université de Haute-Alsace, Metsähovi Radio Observatory, Department of Electronics and Nanoengineering, Aalto-yliopisto, and Aalto University
Subjects: quasars: individual (3C 273, statistical [Methods], 010504 meteorology & atmospheric sciences, active [Galaxies], Astrophysics::High Energy Astrophysical Phenomena, galaxies: active, TIME-SERIES, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, 3C 345, 3C 454.3), 0103 physical sciences, MULTIFREQUENCY OBSERVATIONS, Autoregressive integrated moving average, MULTIWAVELENGTH OBSERVATIONS, 010303 astronomy & astrophysics, Scaling, Luminosity function, 0105 earth and related environmental sciences, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, methods: statistical, WAVELET TRANSFORM, Wavelet transform, Astronomy and Astrophysics, Quasar, Multifractal system, Rest frame, FLARING BEHAVIOR, Light curve, Astrophysics - Astrophysics of Galaxies, 3C 454.3, 3C 279, individual (3C 273, 3C 279, 3C 345, 3C 454.3) [Quasars], GAMMA-RAY, LUMINOSITY FUNCTION, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), X-RAY, OPTICAL VARIABILITY, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Variations in scaling behavior in the flux and emissions of distant astronomical sources with respect to their cosmic time are important l phenomena that can provide valuable information about the dynamics within the sources and their cosmological evolution with time. Different studies have been applying linear analysis to understand and model quasars' light curves. Here, we study the multifractal behavior of selected quasars' radio emissions in their observed frame (at 22 and 37 GHz bands) and and their rest frame. To this end, we apply the wavelet transform-based multifractal analysis formalism called wavelet transform modulus maxima. In addition, we verify whether the autoregressive integrated moving average (ARIMA) models fit our data or not. In our work, we observe strong multifractal behavior for all the sources. Additionally, we find that the degree of multifractality is strongly similar for each source and significantly different between sources at 22 and 37 GHz. This similarity implies that the two frequencies have the same radiation region and mechanism, whereas the difference indicates that the sources have intrinsically different dynamics. Furthermore, we show that the degree of multifractality is the same in the observed and rest frames of the quasars, i.e., multifractality is an intrinsic property of radio quasars. Finally, we show that the ARIMA models fit the 3C 345 quasar at 22 GHz and partially fit most of the time series with the exception of the 3C 273 and 3C 279 quasars at 37 GHz, for which the models are found to be inadequate., Comment: 24 pages, 14 figures, Accepted for publication in The Astrophysical Journal
Published: 2019

24. Temporal and spectral evolutionary features of gamma-ray bursts detected by theFermiGamma-Ray Space Telescope

Author: Tak, Donggeun
Subjects: Large area telescope, Astrophysics::High Energy Astrophysical Phenomena, Fermi gamma-ray space telescope, gamma-ray burst, gamma-ray, relativistic jet, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics
Abstract: Gamma-ray bursts (GRBs) are the most powerful electromagnetic events in universe. GRBs are powered by either core-collapse of massive stars or binary mergers of two compact objects. These progenitor systems are believed to launch relativistic, collimated jets, which produce short, bright gamma-ray flashes (prompt emission) and long-lived, fading emission (afterglow) in the broad energy band from radio to gamma-rays. Even though the characteristics of the prompt emission and the afterglow have been vigorously studied, many details of the physics of GRBs remain uncertain. The Fermi Gamma-ray Space Telescope(Fermi) provides invaluable data for studying GRBs with the help of a very wide field of view and broad energy coverage from the hard X-ray to gamma-ray band. Fermi consists of two instruments, the Gamma-ray Burst Monitor (GBM; 8 keV–40 MeV) and the Large Area Telescope(LAT; 20 MeV– >300 GeV). In this thesis, I present dedicated analysis results on three bright GRBs: GRB 131108A, GRB 160709A, and GRB 190114C. Each of them shows its own evolution that includes the unusual and general features of GRBs. In addition, I performed two systematic studies using the full 10 year samples of LAT and GBM detected GRBs. For the first, I focused on the high-energy emission (>100 MeV) and its origin by tracking its temporal and spectral evolution. In the second, focusing on the prompt emission phase, I found an observational signature that originates in the geometry of the relativistic jet, which had been predicted but was previously unobserved.
Published: 2019
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25. Theoretical Study of Gamma-ray Pulsars

Author: Yuzhe Song, Jumpei Takata, and K. S. Cheng
Subjects: Physics, Photon, lcsh:Astronomy, 010308 nuclear & particles physics, Scattering, Astrophysics::High Energy Astrophysical Phenomena, Gamma ray, General Physics and Astronomy, Magnetosphere, Astronomy, Astrophysics, 01 natural sciences, Binary pulsar, lcsh:QB1-991, Pulsar, Millisecond pulsar, 0103 physical sciences, General Earth and Planetary Sciences, gamma-ray, 010303 astronomy & astrophysics, pulsar, X-ray pulsar
Abstract: We use the non-stationary three dimensional two-layer outer gap model to explain gamma-ray emissions from a pulsar magnetosphere. We found out that for some pulsars like the Geminga pulsar, it was hard to explain emissions above a level of around 1 GeV. We then developed the model into a non-stationary model. In this model we assigned a power-law distribution to one or more of the spectral parameters proposed in the previous model and calculated the weighted phase-averaged spectrum. Though this model is suitable for some pulsars, it still cannot explain the high energy emission of the Geminga pulsar. An Inverse-Compton Scattering component between the primary particles and the radio photons in the outer magnetosphere was introduced into the model, and this component produced a sufficient number of GeV photons in the spectrum of the Geminga pulsar.
Published: 2016

26. VHE emission from the vicinity of SMBH: the disk-magnetosphere connection.

Author: Pedaletti, G., Wagner, S. J., and Bicknell, G. V.
Subjects: *SUPERMASSIVE stars, *SUPERMASSIVE black holes, *MAGNETOSPHERE, *MAGNETIC fields, *ACCRETION (Astrophysics), *ASTROPHYSICS
Abstract: High energy and very high energy (VHE; >10 GeV) γ-rays are expected to be produced from the vicinity of super-massive black holes (SMBH). In the magnetosphere of a spinning black hole acceleration of particles will take place in the field gaps. VHE emission from these particles is feasible via several processes. Systems surrounded by a low photon field will allow the emission to escape. In order to predict the level of emission of these systems, the mass of the central object and the intensity of the magnetic field need to be known. An estimate of the magnetic field is obtained here using the connection between BH magnetosphere and the magnetized accretion disk. Predicted fluxes and energy domain of the corresponding VHE emission are discussed. [ABSTRACT FROM AUTHOR]
Published: 2008
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27. GLAST LAT Searches for Particle Dark Matter: An Experimental Point of View.

Author: Wai, Lawrence L.
Subjects: *DARK matter, *INTERSTELLAR medium, *ASTROPHYSICS, *SPACE environment, *GAMMA rays, *ELECTROMAGNETIC waves
Abstract: The Gamma-ray Large Area Space Telescope (GLAST) Large Area Telescope (LAT) has the opportunity to contribute to the discovery of the nature of dark matter, mainly if dark matter is composed of new Weakly Interacting Massive Particles (WIMPs). We outline the basic signatures, strategies, and experimental challenges for dark matter detection. We describe the various search techniques being developed within GLAST and how they compare with one another. We discuss the future need for precision follow-up observations of potential GLAST dark matter sources. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]
Published: 2007
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28. Unraveling the Complex Behavior of Mrk 421 with Simultaneous X-Ray and VHE Observations during an Extreme Flaring Activity in 2013 April

Author: Simonetta Puccetti, D. Dominis Prester, M. Makariev, Alice Donini, Sofia O. Kurtanidze, G. Bonnoli, Julian Sitarek, D. Dorner, Yoshiki Ohtani, J. Becerra González, S. Ventura, S. Ansoldi, L. Nogués, J. Besenrieder, A. Rugliancich, P. Munar-Adrover, Jose Luis Contreras, B. Jordan, I. Puljak, Pawel Gliwny, L. V. Larionova, L. Di Venere, Sunay Ibryamov, Abelardo Moralejo, M. I. Martínez, B. De Lotto, Juan Cortina, A. A. Mokrushina, E. Moretti, Kaya Mori, Maria Petropoulou, Elena G. Larionova, J. Rico, Juan Abel Barrio, Narek Sahakyan, A. Fattorini, C. Fruck, F. Del Puppo, F. Verrecchia, Victoria Moreno, Chiara Righi, M. V. Fonseca, Elina Lindfors, Justin D. Finke, D. A. Morozova, V. D'Elia, A. López-Oramas, M. G. Nikolashvili, John Hoang, Susumu Inoue, L. Maraschi, R. Paoletti, R. Reinthal, A. Strigachev, Saverio Lombardi, T. Schweizer, E. Do Souto Espiñeira, Tomislav Terzić, Ferdinando Giordano, Fabrizio Tavecchio, C. Nigro, B. Banerjee, Bernd Schleicher, A. Hahn, R. G. Chanishvili, Francesco Longo, M. Will, Shunsuke Sakurai, Ll. Font, Takeshi Oka, Davide Depaoli, Alan P. Marscher, L. Saha, D. Elsaesser, Antonio Stamerra, R. Carosi, G. Ceribella, Joni Tammi, V. Fallah Ramazani, D. Lelas, T. Guever, M. Teshima, J. M. Paredes, Dorota Sobczyńska, Zeljka Bosnjak, Chakali Eswaraiah, A. C. R. Readhead, G. Busetto, Jorge Otero-Santos, Mislav Baloković, J. L. Richards, R. A. Chigladze, Y. Chai, J. Kushida, Seiya Nozaki, Kari Nilsson, U. Barres de Almeida, L. Foffano, Ciro Bigongiari, Saša Mićanović, V. Vitale, Wen Ping Chen, P. Temnikov, T. Saito, Andrei Berdyugin, David H. Green, D. Strom, F. Di Pierro, E. N. Kopatskaya, Stefano Covino, D. Miceli, S. Gasparyan, D. Blinov, G. Maneva, E. Molina, S. G. Jorstad, T. Surić, M. Mariotti, I. Šnidarić, Satoshi Fukami, H. Kubo, M. Vazquez Acosta, R. López-Coto, Kazuma Ishio, Y. Iwamura, M. Gaug, A. Lamastra, A. C. Sadun, J. Herrera, G. Vanzo, Oscar Blanch, T. S. Grishina, Walter Max-Moerbeck, Anne Lähteenmäki, S. M. Colak, Valeri M. Larionov, C. M. Raiteri, C. Maggio, O. M. Kurtanidze, S. Cikota, D. Ninci, G. Ferrara, A. De Angelis, Rumen Bachev, Yu. V. Troitskaya, M. Minev, Georgi Latev, Elisa Bernardini, Other groups, L. Pavletić, Elisa Prandini, Goran Damljanović, Evgeni Semkov, M. Delfino, Wolfgang Rhode, Yusuke Suda, Massimo Persic, Carlo Vigorito, A. Berti, Paul S. Smith, K. Noda, Dario Hrupec, C. Leto, Victor A. Acciari, K. Nishijima, B. Machado de Oliveira Fraga, Mitsunari Takahashi, P. Peñil, L. Bellizzi, Serena Loporchio, Jose Miguel Miranda, N. Godinović, M. Strzys, Ashot Chilingarian, N. Giglietto, U. Colin, W. Bednarek, Simone Mender, Moritz Hütten, W. Bhattacharyya, I. Agudo, R. Mirzoyan, Louis Antonelli, Dominik Baack, P. Majumdar, G. M. Madejski, A. Arbet Engels, Vitaly Neustroev, J. W. Moody, Luca Tosti, M. Villata, D. Morcuende, N. Torres-Albà, I. Vovk, Jordi Delgado, H. C. Lin, Kevin Schmidt, Talvikki Hovatta, D. Hadasch, M. Palatiello, Y. Kajiwara, Francesco Dazzi, M. Mallamaci, O. Vince, M. Peresano, Yosuke Kobayashi, P. Da Vela, F. D'Ammando, K. Mannheim, R. J. García López, Ivan S. Troitsky, Tjark Miener, David Paneque, A. Biland, Marina Manganaro, P. G. Prada Moroni, Merja Tornikoski, Matteo Cerruti, M. López, Konstancja Satalecka, D. Mazin, Michele Doro, J. Barnes, F. Leone, M. Ribó, J. van Scherpenberg, A. Babić, Alessia Spolon, Léa Jouvin, Manasvita Joshi, Vassil Verguilov, Daniel Kerszberg, V. Ramakrishnan, D. Zarić, Tomohiro Inada, E. Colombo, M. Perri, M. Garczarczyk, Federal Ministry of Education and Research (Germany), Istituto Nazionale di Astrofisica, Swiss National Science Foundation, Istituto Nazionale di Fisica Nucleare, Ministerio de Economía y Competitividad (España), European Commission, Department of Atomic Energy (India), Ministry of Education, Culture, Sports, Science and Technology (Japan), Japan Society for the Promotion of Science, Ministry of Education, Youth and Science (Bulgaria), Academy of Finland, Croatian Science Foundation, University of Rijeka, German Research Foundation, National Centre for Research and Development (Poland), Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brasil), Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, National Aeronautics and Space Administration (US), Department of Energy (US), Centre National de la Recherche Scientifique (France), Russian Science Foundation, Gordon and Betty Moore Foundation, John Templeton Foundation, Shota Rustaveli National Science Foundation, Comisión Nacional de Investigación Científica y Tecnológica (Chile), Metsähovi Radio Observatory, Department of Electronics and Nanoengineering, Aalto-yliopisto, Aalto University, Magic, Collaboration, Other Groups And, Collaborator, Acciari, V. A., Ansoldi, S., Antonelli, L. A., Engels, A. A., Baack, D., Babic, A., Banerjee, B., De Almeida, U. B., Barrio, J. A., Gonzalez, J. B., Bednarek, W., Bellizzi, L. K., Bernardini, E., Berti, A., Besenrieder, J., Bhattacharyya, W., Bigongiari, C., Biland, A., Blanch, O., Bonnoli, G., Bosnjak, Z., Busetto, G., Carosi, R., Ceribella, G., Cerruti, M., Chai, Y., Chilingarian, A., Cikota, S., Colak, S. M., Colin, U., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., D'Elia, V., Vela, P. D., Dazzi, F., Angelis, A. D., Lotto, B. D., Puppo, F. D., Delfino, M., Delgado, J., Depaoli, D., Pierro, F. D., Venere, L. D., Souto Espiñeira, E. D., Prester, D. D., Donini, A., Dorner, D., Doro, M., Elsaesser, D., Ramazani, V. F., Fattorini, A., Ferrara, G., Foffano, L., Fonseca, M. V., Font, L., Fruck, C., Fukami, S., Lopez, R. J. G., Garczarczyk, M., Gasparyan, S., Gaug, M., Giglietto, N., Giordano, F., Gliwny, P., Godinovic, N., Green, D., Hadasch, D., Hahn, A., Hassan, T., Herrera, J., Hoang, J., Hrupec, D., Hutten, M., Inada, T., Inoue, S., Ishio, K., Iwamura, Y., Jouvin, L., Kajiwara, Y., Kerszberg, D., Kobayashi, Y., Kubo, H., Kushida, J., Lamastra, A., Lelas, D., Leone, F., Lindfors, E., Lombardi, S., Longo, F., Lopez, M., Lopez-Coto, R., Lopez-Oramas, A., Loporchio, S., De Oliveira Fraga, B. M., Maggio, C., Majumdar, P., Makariev, M., Mallamaci, M., Maneva, G., Manganaro, M., Mannheim, K., Maraschi, L., Mariotti, M., Martinez, M., Mazin, D., Mender, S., Micanovic, S., Miceli, D., Miener, T., Minev, M., Miranda, J. M., Mirzoyan, R., Molina, E., Moralejo, A., Morcuende, D., Moreno, V., Moretti, E., Munar-Adrover, P., Neustroev, V., Nigro, C., Nilsson, K., Ninci, D., Nishijima, K., Noda, K., Nogues, L., Nozaki, S., Ohtani, Y., Oka, T., Otero-Santos, J., Palatiello, M., Paneque, D., Paoletti, R., Paredes, J. M., Pavletic, L., Peñil, P., Peresano, M., Persic, M., Moroni, P. G. P., Prandini, E., Puljak, I., Rhode, W., Ribo, M., Rico, J., Righi, C., Rugliancich, A., Saha, L., Sahakyan, N., Saito, T., Sakurai, S., Satalecka, K., Schleicher, B., Schmidt, K., Schweizer, T., Sitarek, J., Snidaric, I., Sobczynska, D., Spolon, A., Stamerra, A., Strom, D., Strzys, M., Suda, Y., Suric, T., Takahashi, M., Tavecchio, F., Temnikov, P., Terzic, T., Teshima, M., Torres-Alba, N., Tosti, L., Scherpenberg, J. V., Vanzo, G., Acosta, M. V., Ventura, S., Verguilov, V., Vigorito, C. F., Vitale, V., Vovk, I., Will, M., Zaric, D., Petropoulou, M., Finke, J., D'Ammando, F., Balokovic, M., Madejski, G., Mori, K., Puccetti, S., Leto, C., Perri, M., Verrecchia, F., Villata, M., Raiteri, C. M., Agudo, I., Bachev, R., Berdyugin, A., Blinov, D. A., Chanishvili, R., Chen, W. P., Chigladze, R., Damljanovic, G., Eswaraiah, C., Grishina, T. S., Ibryamov, S., Jordan, B., Jorstad, S. G., Joshi, M., Kopatskaya, E. N., Kurtanidze, O. M., Kurtanidze, S. O., Larionova, E. G., Larionova, L. V., Larionov, V. M., Latev, G., Lin, H. C., Marscher, A. P., Mokrushina, A. A., Morozova, D. A., Nikolashvili, M. G., Semkov, E., Smith, P. S., Strigachev, A., Troitskaya, Y. V., Troitsky, I. S., Vince, O., Barnes, J., Guver, T., Moody, J. W., Sadun, A. C., Hovatta, T., Richards, J. L., Max-Moerbeck, W., Readhead, A. C. S., Lahteenmaki, A., Tornikoski, M., Tammi, J., Ramakrishnan, V., and Reinthal, R.
Subjects: Individual sources Mrk 421, Flux, Astrophysics, Blazar, 7. Clean energy, 01 natural sciences, Imaging Atmospheric Cherenkov observations, Gamma-ray, Active galaxie, Relativistic jet, MAGIC (telescope), BL lacertae objects, BL Lacertae objects, Blazars, Active galaxies, Markarian galaxies, Gamma-ray detectors, Gamma-rays, Relativistic jets, High energy astrophysics, Observational astronomy, 010303 astronomy & astrophysics, astro-ph.HE, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Gamma ray, X-ray, Markarian galaxie, Física nuclear, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics and Astronomy, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics - High Energy Astrophysical Phenomena, Individual sources Mrk 421, Imaging Atmospheric Cherenkov observations, MAGIC, BL Lacertae objects, Blazars, Active galaxies, Markarian galaxies, Gamma-ray detectors, Gamma-rays, Relativistic jets, High energy astrophysics, Observational astronomy, Plasmoid, Astrophysics::Cosmology and Extragalactic Astrophysics, BL Lacertae object, High energy astrophysic, 0103 physical sciences, Gamma-ray detector, 010308 nuclear & particles physics, Astronomy and Astrophysics, Magnetic reconnection, Light curve, MAGIC, 13. Climate action, Space and Planetary Science, ddc:520, High Energy Astrophysical Phenomena
Abstract: We report on a multiband variability and correlation study of the TeV blazar Mrk 421 during an exceptional flaring activity observed from 2013 April 11 to 19. The study uses, among others, data from GLAST-AGILE Support Program (GASP) of the Whole Earth Blazar Telescope (WEBT), Swift, Nuclear Spectroscopic Telescope Array (NuSTAR), Fermi Large Area Telescope, Very Energetic Radiation Imaging Telescope Array System (VERITAS), and Major Atmospheric Gamma Imaging Cherenkov (MAGIC). The large blazar activity and the 43 hr of simultaneous NuSTAR and MAGIC/VERITAS observations permitted variability studies on 15 minute time bins over three X-ray bands (3-7 keV, 7-30 keV, and 30-80 keV) and three very-high-energy (VHE; >0.1 TeV) gamma-ray bands (0.2-0.4 TeV, 0.4-0.8 TeV, and >0.8 TeV). We detected substantial flux variations on multi-hour and sub-hour timescales in all of the X-ray and VHE gamma-ray bands. The characteristics of the sub-hour flux variations are essentially energy independent, while the multi-hour flux variations can have a strong dependence on the energy of the X-rays and the VHE gamma-rays. The three VHE bands and the three X-ray bands are positively correlated with no time lag, but the strength and characteristics of the correlation change substantially over time and across energy bands. Our findings favor multi-zone scenarios for explaining the achromatic/chromatic variability of the fast/slow components of the light curves, as well as the changes in the flux-flux correlation on day-long timescales. We interpret these results within a magnetic reconnection scenario, where the multi-hour flux variations are dominated by the combined emission from various plasmoids of different sizes and velocities, while the sub-hour flux variations are dominated by the emission from a single small plasmoid moving across the magnetic reconnection layer. © 2020. The American Astronomical Society. All rights reserved., The financial support of the German BMBF and MPG, the Italian INFN and INAF, the Swiss National Fund SNF, the ERDF under the Spanish MINECO (FPA2017-87859-P, FPA2017-85668-P, FPA2017-82729-C6-2-R, FPA2017-827 29-C6-6-R, FPA2017-82729-C6-5-R, AYA2015-71042-P, AYA2016-76012-C3-1-P, ESP2017-87055-C2-2-P, and FPA 201790566REDC), the Indian Department of Atomic Energy, the Japanese JSPS and MEXT, the Bulgarian Ministry of Education and Science, National RI Roadmap Project DO-1153/28.08.2018 and the Academy of Finland grant No. 320045 is gratefully acknowledged. This work was also supported by the Spanish Centro de Excelencia "Severo Ochoa" SEV-20160588 and SEV-2015-0548, and Unidad de Excelencia "Maria de Maeztu" MDM-2014-0369, by the Croatian Science Foundation (HrZZ) Project IP-2016-06-9782 and the University of Rijeka Project 13.12.1.3.02, by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3, the Polish National Research Centre grant UMO-2016/22/M/ST9/00382, and by the Brazilian MCTIC, CNPq and FAPERJ. The Fermi-LAT.Collaboration acknowledges generous ongoing support from a number of agencies and institutes that have supported both the development and the operation of the LAT as well as scientific data analysis. These include the National Aeronautics and Space Administration and the Department of Energy in the United States, the Commissariat a l'Energie Atomique and the Centre National de la Recherche Scientifique/Institut National de Physique Nucleaire et de Physique des Particules in France, the Agenzia Spaziale Italiana and the Istituto Nazionale di Fisica Nucleare in Italy, the Ministry of Education, Culture, Sports, Science and Technology (MEXT), High Energy Accelerator Research Organization (KEK), and Japan Aerospace Exploration Agency (JAXA) in Japan, and the K..A..Wallenberg Foundation, the Swedish Research Council, and the Swedish National Space Board in Sweden. Additional support for science analysis during the operations phase is gratefully acknowledged from the Istituto Nazionale di Astrofisica in Italy and the Centre National d'Etudes Spatiales in France. This work made use of data from the NuSTAR mission, a project led by the California Institute of Technology, managed by the Jet Propulsion Laboratory, and funded by the National Aeronautics and Space Administration. We thank the NuSTAR Operations, Software, and Calibration teams for support with the execution and analysis of these observations. This research has made use of the NuSTAR Data Analysis Software (NuSTARDAS) jointly developed by the ASI Science Data Center (ASDC; Italy) and the California Institute of Technology (USA). D.P. and A.B. are grateful to Amy Furniss and Wystan Benbow for providing the VERITAS VHE gamma-ray fluxes and for useful discussions about them. M.P. acknowledges support from the Lyman Jr. Spitzer Postdoctoral Fellowship and NASA Fermi grant No. 80NSSC18K1745., and J.F. is partially supported by NASA under contract S-15633Y. M.B. acknowledges support from NASA Headquarters under the NASA Earth and Space Science Fellowship Program (grant NNX14AQ07H) and the black hole Initiative at Harvard University, which is funded in part by the Gordon and Betty Moore Foundation (grant GBMF8273) and in part by the John Templeton Foundation. This research was partially supported by the Bulgarian National Science Fund of the Ministry of Education and Science under grants DN 18-13/2017, DN 18-10/2017, KP06-H28/3 (2018), and KP-06-PN38/1 (2019), as well as for the Spanish MIMECO (AYA2016-80889-P, RYC-2013-14511) and the IAA-CSIC "Severo Ochoa" program SEV2017-0709. The St. Petersburg University team acknowledges support from Russian Science Foundation grant 17-12-01029. The Abastumani team acknowledges financial support of the project FR/638/6-320/12 by the Shota Rustaveli National Science Foundation under contract 31/77. T.G. acknowledges support from Istanbul University (Project numbers 49429 and 48285), Bilim Akademisi (BAGEP program), and TUBITAK (project numbers 13AT100-431, 13AT100-466, and 13AT60-430). The Boston University effort was supported in part by NASA grants NNX12AO90G and NNX14AQ58G. Data from the Steward Observatory spectropolarimetric monitoring project were used in this paper. This program is supported by Fermi Guest Investigator grants NNX08AW56G, NNX09 AU10G, NNX12AO93G, and NNX15AU81G. The OVRO 40 m monitoring program is supported in part by NASA grants NNX08AW31G and NNX11A043G and NSF grants AST-0808050 and AST-1109911. The Metsahovi team acknowledges the support from the Academy of Finland to our observing projects (numbers 212656, 210338, 121148, and others). W.M. acknowledges support from CONICYT project Basal AFB-170002.
Published: 2020

29. Polarimetric Monitoring of Jets with Kanata Telescope

Author: Koji S. Kawabata, Makoto Uemura, Yasushi Fukazawa, and R. Itoh
Subjects: Physics, 010308 nuclear & particles physics, blazar, optical polarization, gamma-ray, lcsh:Astronomy, Astrophysics::High Energy Astrophysical Phenomena, Polarimetry, Gamma ray, Astronomy and Astrophysics, Optical polarization, Astrophysics, Polarization (waves), 01 natural sciences, law.invention, Telescope, lcsh:QB1-991, Astrophysical jet, law, 0103 physical sciences, Blazar, 010303 astronomy & astrophysics
Abstract: The polarization of relativistic jets is of interest for the understanding of their origin, confinement, and propagation. However, even though numerous measurements have been performed, the mechanisms behind jet variability, creation, and composition are still debated. We have performed simultaneous gamma-ray and optical photopolarimetry observations of 45 blazars with the Kanata telescope since July 2008 to investigate the mechanisms of variability and search for a basic relation between the several subclasses of relativistic jets. Consequently, we found that a correlation between the gamma-ray and optical flux might be related to gamma-ray luminosity, and the maximum polarization degree might be related to gamma-ray luminosity or the ratio of gamma-ray to optical flux. These results imply that low gamma-ray luminosity blazars emit from multiple regions.
Published: 2018

30. The reflection component in the average and heartbeat spectra of the black-hole candidate IGR J17091-3642 during the 2016 outburst

Author: Mariano Mendez, Diego Altamirano, Yanan Wang, Zheng Cheng, Aru Beri, J. M. C. Court, and Astronomy
Subjects: PHASE-RESOLVED SPECTROSCOPY, Astrophysics::High Energy Astrophysical Phenomena, black hole physics, FOS: Physical sciences, Astrophysics, 01 natural sciences, Spectral line, GX 339-4, X-rays: binaries, accretion, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 4U 1630-47, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Spin-½, LIGHT CURVES, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Line-of-sight, Accretion (meteorology), 010308 nuclear & particles physics, Gamma ray, Astronomy and Astrophysics, Radius, Light curve, accretion discs, GAMMA-RAY, Space and Planetary Science, GRS 1915+105, Reflection (physics), Astrophysics::Earth and Planetary Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, X-RAY BINARIES, ACCRETION DISC, COLD MATTERXMM-NEWTON
Abstract: We present simultaneous NuSTAR and Swift observations of the black hole transient IGR J17091-3642 during its 2016 outburst. By jointly fitting six NuSTAR and four Swift spectra, we found that during this outburst the source evolves from the hard to the hard/soft intermediate and back to the hard state, similar to the 2011 outburst. Unlike in the previous outburst, in this case we observed both a broad emission and an moderately broad absorption line in our observations. Our fits favour an accretion disc with an inclination angle of $\sim$$45\deg$ with respect to the line of sight and a high iron abundance of $3.5\pm0.3$ in units of the solar abundance. We also observed heartbeat variability in one NuSTAR observation. We fitted the phase-resolved spectra of this observation and found that the reflected emission varies independently from the direct emission, whereas in the fits to the average spectra these two quantities are strongly correlated. Assuming that in IGR J17091-3642 the inner radius of the disc both in the average and the phase-resolved spectra is located at the radius of the innermost stable circular orbit, with 90% confidence the spin parameter of the black hole in this system is $-0.13\leq a_{*}\leq0.27$., Comment: 14 pages, 12 figures
Published: 2018
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31. Fermi-LAT Observations of LIGO/Virgo Event GW170817

Author: G. Chiaro, Marco Ajello, Diego F. Torres, Stefano Ciprini, J. B. Thayer, G. Jóhannesson, E. Moretti, Eleonora Troja, Nicola Omodei, Ronaldo Bellazzini, R. Buehler, E. J. Siskind, J. F. Ormes, Chong Yang, L. Guillemot, E. Orlando, T. J. Brandt, Stefan Funk, J. Li, Peter F. Michelson, Magnus Axelsson, L. R. Cominsky, Igor V. Moskalenko, Elliott D. Bloom, S. Cutini, A. A. Moiseev, Marcello Giroletti, Olaf Reimer, D. Horan, F. Loparco, Carmelo Sgrò, Riccardo Rando, A. Chekhtman, Johan Bregeon, P. Lubrano, Francesco Longo, I. A. Grenier, E. Cavazzuti, David H. Green, R. A. Cameron, J. L. Racusin, A. Reimer, Nicola Giglietto, E. Nuss, David Paneque, C. Favuzzi, Gloria Spandre, M. Kuss, Vahé Petrosian, Giacomo Principe, James Chiang, F. de Palma, F. Gargano, Johann Cohen-Tanugi, P. Fusco, L. Di Venere, Roger Blandford, Hiroyasu Tajima, Roopesh Ojha, Gabrijela Zaharijas, Denis Bastieri, Luca Latronico, K. S. Wood, J. G. Thayer, M. Di Mauro, Gino Tosti, D. Dumora, Elizabeth C. Ferrara, B. Berenji, Giacomo Vianello, M. N. Lovellette, P. A. Caraveo, J. M. Casandjian, R. Bonino, J. Granot, Steven Ritz, D. J. Suson, T. H. Burnett, C. C. Cheung, F. Piron, J. Valverde, Alice K. Harding, Melissa Pesce-Rollins, Tonia M. Venters, G. La Mura, Regina Caputo, N. Di Lalla, Luca Baldini, M. Takahashi, M. Palatiello, M. E. Monzani, M. N. Mazziotta, D. Tak, Sylvain Guiriec, R. Gill, Anna Franckowiak, D. Costantin, S. Rainò, Tsunefumi Mizuno, Vaidehi S. Paliya, Yasushi Fukazawa, P. M. Saz Parkinson, J. D. Magill, Soebur Razzaque, Alice Allafort, Elisabetta Bissaldi, P. Bruel, Matthew G. Baring, Sara Buson, T. A. Porter, Daniel Kocevski, Fumiya Imazato, T. Glanzman, R. Dubois, E. Hays, P. Spinelli, Francesco Giordano, F. Spada, Eugenio Bottacini, Alberto Manfreda, Dario Gasparrini, Stefan Larsson, M. Razzano, Filippo D'Ammando, Alessandro Cuoco, M.-H. Grondin, S. Maldera, T. Kamae, Eleonora Torresi, Massimo Persic, Felix Ryde, Guido Barbiellini, L. S. Rochester, S. Kensei, Matteo Negro, A. Morselli, ITA, Laboratoire Univers et Particules de Montpellier (LUPM), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Ajello, M., Allafort, A., Axelsson, M., Baldini, L., Barbiellini, G., Baring, M. G., Bastieri, D., Bellazzini, R., Berenji, B., Bissaldi, E., Blandford, R. D., Bloom, E. D., Bonino, R., Bottacini, E., Brandt, T. J., Bregeon, J., Bruel, P., Buehler, R., Burnett, T. H., Buson, S., Cameron, R. A., Caputo, R., Caraveo, P. A., Casandjian, J. M., Cavazzuti, E., Chekhtman, A., Cheung, C. C., Chiang, J., Chiaro, G., Ciprini, S., Cohen-Tanugi, J., Cominsky, L. R., Costantin, D., Cuoco, A., Cutini, S., D'Ammando, F., Palma, F. De, Lalla, N. Di, Mauro, M. Di, Venere, L. Di, Dubois, R., Dumora, D., Favuzzi, C., Ferrara, E. C., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Giglietto, N., Gill, R., Giordano, F., Giroletti, M., Glanzman, T., Granot, J., Green, D., Grenier, I. A., Grondin, M. -H., Guillemot, L., Guiriec, S., Harding, A. K., Hays, E., Horan, D., Imazato, F., Jóhannesson, G., Kamae, T., Kensei, S., Kocevski, D., Kuss, M., Mura, G. La, Larsson, S., Latronico, L., Li, J., Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Magill, J. D., Maldera, S., Manfreda, A., Mazziotta, M. N., Michelson, P. F., Mizuno, T., Moiseev, A. A., Monzani, M. E., Moretti, E., Morselli, A., Moskalenko, I. V., Negro, M., Nuss, E., Ojha, R., Omodei, N., Orlando, E., Ormes, J. F., Palatiello, M., Paliya, V. S., Paneque, D., Persic, M., Pesce-Rollins, M., Petrosian, V., Piron, F., Porter, T. A., Principe, G., Racusin, J. L., Raino, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Ritz, S., Rochester, L. S., Ryde, F., Parkinson, P. M. Saz, Sgro, C., Siskind, E. J., Spada, F., Spandre, G., Spinelli, P., Suson, D. J., Tajima, H., Takahashi, M., Tak, D., Thayer, J. G., Thayer, J. B., Torres, D. F., Torresi, E., Tosti, G., Troja, E., Valverde, J., Venters, T. M., Vianello, G., Wood, K., Yang, C., Zaharijas, G., Raunvísindastofnun (HÍ), Science Institute (UI), Verkfræði- og náttúruvísindasvið (HÍ), School of Engineering and Natural Sciences (UI), Háskóli Íslands, University of Iceland, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES)
Subjects: neutron star: binary, Gammageislar, gamma-ray burst: general, Astrophysics, general [gamma-ray burst], 01 natural sciences, Gamma-ray, Luminosity, gamma rays: general, gravitational waves, gamma ray: flux, LIGO, gravitational wave, 010303 astronomy & astrophysics, Physics, energy: high, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Gamma-ray burst: general, Astrophysics::High Energy Astrophysical Phenomena, Context (language use), Astrophysics::Cosmology and Extragalactic Astrophysics, gamma ray: burst, gravitational radiation: direct detection, GLAST, Gravitational waves, binary: coalescence, 0103 physical sciences, ddc:530, 010306 general physics, Gamma-ray burst, Astrophysics::Galaxy Astrophysics, Gravitational wave, Astronomy and Astrophysics, trigger, Astronomy and Astrophysic, Stjarneðlisfræði, redshift, Redshift, gravitational radiation detector, Neutron star, electromagnetic, VIRGO, [SDU]Sciences of the Universe [physics], Space and Planetary Science, gravitational radiation: emission, ddc:520, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], general [gamma rays], Fermi Gamma-ray Space Telescope
Abstract: Publisher's version (útgefin grein), We present the Fermi Large Area Telescope (LAT) observations of the binary neutron star merger event GW170817 and the associated short gamma-ray burst (SGRB) GRB 170817A detected by the Fermi Gamma-ray Burst Monitor. The LAT was entering the South Atlantic Anomaly at the time of the LIGO/Virgo trigger (t GW) and therefore cannot place constraints on the existence of high-energy (E > 100 MeV) emission associated with the moment of binary coalescence. We focus instead on constraining high-energy emission on longer timescales. No candidate electromagnetic counterpart was detected by the LAT on timescales of minutes, hours, or days after the LIGO/Virgo detection. The resulting flux upper bound (at 95% C.L.) from the LAT is 4.5 × 10−10 erg cm−2 s−1 in the 0.1–1 GeV range covering a period from t GW + 1153 s to t GW + 2027 s. At the distance of GRB 170817A, this flux upper bound corresponds to a luminosity upper bound of 9.7 × 1043 erg s−1, which is five orders of magnitude less luminous than the only other LAT SGRB with known redshift, GRB 090510. We also discuss the prospects for LAT detection of electromagnetic counterparts to future gravitational-wave events from Advanced LIGO/Virgo in the context of GW170817/GRB 170817A., This work performed in part under DOE Contract DE-AC02-76SF00515.
Published: 2018

32. An extreme magneto-ionic environment associated with the fast radio burst source FRB 121102

Author: George Heald, F. Fernandez, Laura Spitler, Elizabeth A. K. Adams, Daniele Michilli, Robert Wharton, Casey Brinkman, P. J. Van Rooy, Geoffrey C. Bower, Vishal Gajjar, Gregory Hellbourg, Charlotte Sobey, Benito Marcote, T. J. W. Lazio, Casey J. Law, D. Whitlow, A. Seymour, Shriharsh P. Tendulkar, Scott M. Ransom, C. G. Bassa, V. M. Kaspi, Andrew Siemion, Maura McLaughlin, R. S. Lynch, James M. Cordes, Paul Demorest, K. Gourdji, Zsolt Paragi, Jason W. T. Hessels, Anne M. Archibald, Shami Chatterjee, Natasha Maddox, P. Scholz, Slavko Bogdanov, High Energy Astrophys. & Astropart. Phys (API, FNWI), API Other Research (FNWI), and Astronomy
Subjects: POLARIZATION, Astrophysics::High Energy Astrophysical Phenomena, Astronomy, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, SAGITTARIUS-A-ASTERISK, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Supernova remnant, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Nebula, Multidisciplinary, 010308 nuclear & particles physics, Fast radio burst, Canadian Hydrogen Intensity Mapping Experiment, FARADAY-ROTATION, FIELDS, Redshift, Black hole, CRAB-NEBULA, Neutron star, Crab Nebula, GAMMA-RAY, HOST GALAXY, SUPERNOVA REMNANT, BLACK-HOLE, X-RAY, Astrophysics - High Energy Astrophysical Phenomena
Abstract: Fast radio bursts (FRBs) are millisecond-duration, extragalactic radio flashes of unknown physical origin. FRB 121102, the only known repeating FRB source, has been localized to a star-forming region in a dwarf galaxy at redshift z = 0.193, and is spatially coincident with a compact, persistent radio source. The origin of the bursts, the nature of the persistent source, and the properties of the local environment are still debated. Here we present bursts that show ~100% linearly polarized emission at a very high and variable Faraday rotation measure in the source frame: RM_src = +1.46 x 10^5 rad m^-2 and +1.33 x 10^5 rad m^-2 at epochs separated by 7 months, in addition to narrow (< 30 mus) temporal structure. The large and variable rotation measure demonstrates that FRB 121102 is in an extreme and dynamic magneto-ionic environment, while the short burst durations argue for a neutron star origin. Such large rotation measures have, until now, only been observed in the vicinities of massive black holes (M_BH > 10^4 MSun). Indeed, the properties of the persistent radio source are compatible with those of a low-luminosity, accreting massive black hole. The bursts may thus come from a neutron star in such an environment. However, the observed properties may also be explainable in other models, such as a highly magnetized wind nebula or supernova remnant surrounding a young neutron star., Published in Nature: DOI: 10.1038/nature25149
Published: 2018

33. Constraints on Galactic Neutrino Emission with Seven Years of IceCube Data

Author: IceCube Collaboration, Aartsen, M. G., Ackermann, M., Adams, J., Aguilar, J. A., Ahlers, M., Ahrens, M., Samarai, I. Al, Altmann, D., Andeen, K., Anderson, T., Ansseau, I., Anton, G., Argüelles, C., Auffenberg, J., Axani, S., Bagherpour, H., Bai, X., Barron, J. P., Barwick, S. W., Baum, V., Bay, R., Beatty, J. J., Tjus, J. Becker, Becker, K. -H., BenZvi, S., Berley, D., Bernardini, E., Besson, D. Z., Binder, G., Bindig, D., Blaufuss, E., Blot, S., Bohm, C., Börner, M., Bos, F., Bose, D., Böser, S., Botner, O., Bourbeau, J., Bradascio, F., Braun, J., Brayeur, L., Brenzke, M., Bretz, H. -P., Bron, S., Burgman, A., Carver, T., Casey, J., Casier, M., Cheung, E., Chirkin, D., Christov, A., Clark, K., Classen, L., Coenders, S., Collin, G. H., Conrad, J. M., Cowen, D. F., Cross, R., Day, M., de André, J. P. A. M., De Clercq, C., DeLaunay, J. J., Dembinski, H., De Ridder, S., Desiati, P., de Vries, K. D., de Wasseige, G., de With, M., DeYoung, T., Díaz-Vélez, J. C., di Lorenzo, V., Dujmovic, H., Dumm, J. P., Dunkman, M., Eberhardt, B., Ehrhardt, T., Eichmann, B., Eller, P., Evenson, P. A., Fahey, S., Fazely, A. R., Felde, J., Filimonov, K., Finley, C., Flis, S., Franckowiak, A., Friedman, E., Fuchs, T., Gaisser, T. K., Gallagher, J., Gerhardt, L., Ghorbani, K., Giang, W., Glauch, T., Glüsenkamp, T., Goldschmidt, A., Gonzalez, J. G., Grant, D., Griffith, Z., Haack, C., Hallgren, A., Halzen, F., Hanson, K., Hebecker, D., Heereman, D., Helbing, K., Hellauer, R., Hickford, S., Hignight, J., Hill, G. C., Hoffman, K. D., Hoffmann, R., Hokanson-Fasig, B., Hoshina, K., Huang, F., Huber, M., Hultqvist, K., In, S., Ishihara, A., Jacobi, E., Japaridze, G. S., Jeong, M., Jero, K., Jones, B. J. P., Kalacynski, P., Kang, W., Kappes, A., Karg, T., Karle, A., Katz, U., Kauer, M., Keivani, A., Kelley, J. L., Kheirandish, A., Kim, J., Kim, M., Kintscher, T., Kiryluk, J., Kittler, T., Klein, S. R., Kohnen, G., Koirala, R., Kolanoski, H., Köpke, L., Kopper, C., Kopper, S., Koschinsky, J. P., Koskinen, D. J., Kowalski, M., Krings, K., Kroll, M., Krückl, G., Kunnen, J., Kunwar, S., Kurahashi, N., Kuwabara, T., Kyriacou, A., Labare, M., Lanfranchi, J. L., Larson, M. J., Lauber, F., Lennarz, D., Lesiak-Bzdak, M., Leuermann, M., Liu, Q. R., Lu, L., Lünemann, J., Luszczak, W., Madsen, J., Maggi, G., Mahn, K. B. M., Mancina, S., Maruyama, R., Mase, K., Maunu, R., McNally, F., Meagher, K., Medici, M., Meier, M., Menne, T., Merino, G., Meures, T., Miarecki, S., Micallef, J., Momenté, G., Montaruli, T., Moore, R. W., Moulai, M., Nahnhauer, R., Nakarmi, P., Naumann, U., Neer, G., Niederhausen, H., Nowicki, S. C., Nygren, D. R., Pollmann, A. Obertacke, Olivas, A., O'Murchadha, A., Palczewski, T., Pandya, H., Pankova, D. V., Peiffer, P., Pepper, J. A., Heros, C. Pérez de los, Pieloth, D., Pinat, E., Plum, M., Price, P. B., Przybylski, G. T., Raab, C., Rädel, L., Rameez, M., Rawlins, K., Reimann, R., Relethford, B., Relich, M., Resconi, E., Rhode, W., Richman, M., Robertson, S., Rongen, M., Rott, C., Ruhe, T., Ryckbosch, D., Rysewyk, D., Sälzer, T., Herrera, S. E. Sanchez, Sandrock, A., Sandroos, J., Sarkar, S., Satalecka, K., Schlunder, P., Schmidt, T., Schneider, A., Schoenen, S., Schöneberg, S., Schumacher, L., Seckel, D., Seunarine, S., Soldin, D., Song, M., Spiczak, G. M., Spiering, C., Stachurska, J., Stanev, T., Stasik, A., Stettner, J., Steuer, A., Stezelberger, T., Stokstad, R. G., Stößl, A., Strotjohann, N. L., Sullivan, G. W., Sutherland, M., Taboada, I., Tatar, J., Tenholt, F., Ter-Antonyan, S., Terliuk, A., Tešić, G., Tilav, S., Toale, P. A., Tobin, M. N., Toscano, S., Tosi, D., Tselengidou, M., Tung, C. F., Turcati, A., Turley, C. F., Ty, B., Unger, E., Usner, M., Vandenbroucke, J., Van Driessche, W., van Eijndhoven, N., Vanheule, S., van Santen, J., Vehring, M., Vogel, E., Vraeghe, M., Walck, C., Wallace, A., Wallraff, M., Wandler, F. D., Wandkowsky, N., Waza, A., Weaver, C., Weiss, M. J., Wendt, C., Westerhoff, S., Whelan, B. J., Wickmann, S., Wiebe, K., Wiebusch, C. H., Wille, L., Williams, D. R., Wills, L., Wolf, M., Wood, J., Wood, T. R., Woolsey, E., Woschnagg, K., Xu, D. L., Xu, X. W., Xu, Y., Yanez, J. P., Yodh, G., Yoshida, S., Yuan, T., Zoll, M., Physics, Elementary Particle Physics, Faculty of Sciences and Bioengineering Sciences, and Vriendenkring VUB
Subjects: FLUX, TELESCOPE, Astrophysics::High Energy Astrophysical Phenomena, gamma rays: ISM, Astronomy and Astrophysics, Space and Planetary Science, FOS: Physical sciences, Flux, Astrophysics, 01 natural sciences, IceCube Neutrino Observatory, ISM [gamma rays], 0103 physical sciences, MILAGRO, DETECTOR, 010303 astronomy & astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Range (particle radiation), Muon, 010308 nuclear & particles physics, Plane (geometry), Galactic plane, Interstellar medium, GAMMA-RAY, Physics and Astronomy, ddc:520, Neutrino, Astrophysics - High Energy Astrophysical Phenomena
Abstract: The origins of high-energy astrophysical neutrinos remain a mystery despite extensive searches for their sources. We present constraints from seven years of IceCube Neutrino Observatory muon data on the neutrino flux coming from the Galactic plane. This flux is expected from cosmic-ray interactions with the interstellar medium or near localized sources. Two methods were developed to test for a spatially-extended flux from the entire plane, both maximum likelihood fits but with different signal and background modeling techniques. We consider three templates for Galactic neutrino emission based primarily on gamma-ray observations and models that cover a wide range of possibilities. Based on these templates and an unbroken $E^{-2.5}$ power-law energy spectrum, we set 90% confidence level upper limits constraining the possible Galactic contribution to the diffuse neutrino flux to be relatively small, less than 14% of the flux reported in Aartsen et al. (2015a) above 1 TeV. A stacking method is also used to test catalogs of known high energy Galactic gamma-ray sources., 14 pages, 4 figures, 4 tables, submitted to The Astrophysical Journal
Published: 2017

34. Investigating powerful jets in radio-loud narrow-line Seyfert 1s

Author: M. Orienti, Daniele Dallacasa, Theodor Isacsson, Justin D. Finke, J. Stoby Hoglund, Filippo D'Ammando, Marcello Giroletti, Josefin Larsson, Orienti, M., D'Ammando, F., Larsson, J., Finke, J., Giroletti, M., Dallacasa, D., Isacsson, T., and Stoby Hoglund, J.
Subjects: ACTIVE GALACTIC NUCLEI, COMPTON ANALYSIS, COMPACT STEEP-SPECTRUM, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Power law, LARGE-AREA TELESCOPE, Spectral line, Luminosity, law.invention, Telescope, law, Blazar, Astrophysics::Galaxy Astrophysics, Line (formation), High Energy Astrophysical Phenomena (astro-ph.HE), Physics, ENERGY-DISTRIBUTION, Astronomy, Astronomy and Astrophysics, PKS 1502+036, Galaxy, GAMMA-RAY, Space and Planetary Science, Brightness temperature, X-RAY, PMN J0948+0022, BL LACERTAE OBJECTS, Astrophysics - High Energy Astrophysical Phenomena
Abstract: We report results on multiband observations from radio to gamma-rays of the two radio-loud narrow-line Seyfert 1 (NLSy1) galaxies PKS 2004-447 and J1548+3511. Both sources show a core-jet structure on parsec scale, while they are unresolved at the arcsecond scale. The high core dominance and the high variability brightness temperature make these NLSy1 galaxies good gamma-ray source candidates. Fermi-LAT detected gamma-ray emission only from PKS 2004-447, with a gamma-ray luminosity comparable to that observed in blazars. No gamma-ray emission is observed for J1548+3511. Both sources are variable in X-rays. J1548+3511 shows a hardening of the spectrum during high activity states, while PKS 2004-447 has no spectral variability. A spectral steepening likely related to the soft excess is hinted below 2 keV for J1548+3511, while the X-ray spectra of PKS 2004-447 collected by XMM-Newton in 2012 are described by a single power-law without significant soft excess. No additional absorption above the Galactic column density or the presence of an Fe line is detected in the X-ray spectra of both sources., 16 pages, 8 figures, accepted for publication in MNRAS
Published: 2015

35. LOFAR discovery of an ultra-steep radio halo and giant head-tail radio galaxy in Abell 1132

Author: F. de Gasperin, D. Rafferty, Annalisa Bonafede, F. Savini, Timothy W. Shimwell, G. Brunetti, Renato Teofilo Giuseppe Morganti, A. O. Clarke, Huib Intema, A. P. Mechev, S. Mandal, Elizabeth K. Mahony, A. Wilber, Marcus Brüggen, Isabella Prandoni, Felipe Andrade-Santos, Huub Röttgering, R. J. van Weeren, Matthias Hoeft, Astronomy, Wilber, A., Brüggen, M., Bonafede, A., Savini, F., Shimwell, T., van Weeren, R.J., Rafferty, D., Mechev, A.P., Intema, H., Andrade-Santos, F., Clarke, A.O., Mahony, E.K., Morganti, R., Prandoni, I., Brunetti, G., Röttgering, H., Mandal, S., de Gasperin, F., and Hoeft, M.
Subjects: SAMPLE, galaxies: clusters: intracluster medium, Radio galaxy, COMA CLUSTER, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, COSMIC-RAY PROTONS, Astrophysics::Cosmology and Extragalactic Astrophysics, ACCELERATION, SCALING RELATIONS, 01 natural sciences, Radio continuum: galaxie, Radio telescope, X-shaped radio galaxy, 0103 physical sciences, HADRONIC MODELS, 010303 astronomy & astrophysics, Galaxy cluster, Astrophysics::Galaxy Astrophysics, Physics, radio continuum: galaxies, REACCELERATION, 010308 nuclear & particles physics, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, LOFAR, Astronomy and Astrophysic, Astrophysics - Astrophysics of Galaxies, galaxies: clusters: individual: Abell 1132, GAMMA-RAY, Radio halo, Space and Planetary Science, galaxies: clusters: general, Astrophysics of Galaxies (astro-ph.GA), Elliptical galaxy, Halo, SKY SURVEY, EMISSION
Abstract: LOFAR observations at 144 MHz have revealed large-scale radio sources in the unrelaxed galaxy cluster Abell 1132. The cluster hosts diffuse radio emission on scales of $\sim$650 kpc near the cluster center and a head-tail (HT) radio galaxy, extending up to 1 Mpc, South of the cluster center. The central diffuse radio emission is not seen in NVSS, FIRST, WENSS, nor in C & D array VLA observations at 1.4 GHz, but is detected in our follow-up GMRT observations at 325 MHz. Using LOFAR and GMRT data, we determine the spectral index of the central diffuse emission to be $\alpha=-1.75\pm0.19$ ($S\propto\nu^{\alpha}$). We classify this emission as an ultra-steep spectrum radio halo and discuss the possible implications for the physical origin of radio halos. The HT radio galaxy shows narrow, collimated emission extending up to 1 Mpc and another 300 kpc of more diffuse, disturbed emission, giving a full projected linear size of 1.3 Mpc - classifying it as a giant radio galaxy (GRG) and making it the longest HT found to date. The head of the GRG coincides with an elliptical galaxy (SDSS J105851.01$+$564308.5) belonging to Abell 1132. In our LOFAR image, there appears to be a connection between the radio halo and the GRG. The turbulence that may have produced the halo may have also affected the tail of the GRG. In turn, the GRG may have provided seed electrons for the radio halo., Comment: Accepted to MNRAS, 12 pages, 8 figures
Published: 2017
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36. Lowering IceCube's energy threshold for point source searches in the southern sky

Author: IceCube Collaboration, Aartsen, M. G., Abraham, K., Ackermann, M., Adams, J., Aguilar, J. A., Ahlers, M., Ahrens, M., Altmann, D., Andeen, K., Anderson, T., Ansseau, I., Anton, G., Archinger, M., Arguelles, C., Arlen, T. C., Auffenberg, J., Axani, S., Bai, X., Barwick, S. W., Baum, V., Bay, R., Beatty, J. J., Tjus, J. Becker, Becker, K. -H., BenZvi, S., Berghaus, P., Berley, D., Bernardini, E., Bernhard, A., Besson, D. Z., Binder, G., Bindig, D., Bissok, M., Blaufuss, E., Blot, S., Boersma, D. J., Bohm, C., B��rner, M., Bos, F., Bose, D., B��ser, S., Botner, O., Braun, J., Brayeur, L., Bretz, H. -P., Burgman, A., Buzinsky, N., Casey, J., Casier, M., Cheung, E., Chirkin, D., Christov, A., Clark, K., Classen, L., Coenders, S., Collin, G. H., Conrad, J. M., Cowen, D. F., Silva, A. H. Cruz, Daughhetee, J., Davis, J. C., Day, M., de Andr��, J. P. A. M., De Clercq, C., Rosendo, E. del Pino, Dembinski, H., De Ridder, S., Desiati, P., de Vries, K. D., de Wasseige, G., de With, M., DeYoung, T., D��az-V��lez, J. C., di Lorenzo, V., Dujmovic, H., Dumm, J. P., Dunkman, M., Eberhardt, B., Ehrhardt, T., Eichmann, B., Euler, S., Evenson, P. A., Fahey, S., Fazely, A. R., Feintzeig, J., Felde, J., Filimonov, K., Finley, C., Flis, S., F��sig, C. -C., Fuchs, T., Gaisser, T. K., Gaior, R., Gallagher, J., Gerhardt, L., Ghorbani, K., Gladstone, L., Glagla, M., Gl��senkamp, T., Goldschmidt, A., Golup, G., Gonzalez, J. G., G��ra, D., Grant, D., Griffith, Z., Ha, C., Haack, C., Ismail, A. Haj, Hallgren, A., Halzen, F., Hansen, E., Hansmann, B., Hansmann, T., Hanson, K., Hebecker, D., Heereman, D., Helbing, K., Hellauer, R., Hickford, S., Hignight, J., Hill, G. C., Hoffman, K. D., Hoffmann, R., Holzapfel, K., Homeier, A., Hoshina, K., Huang, F., Huber, M., Huelsnitz, W., Hultqvist, K., In, S., Ishihara, A., Jacobi, E., Japaridze, G. S., Jeong, M., Jero, K., Jones, B. J. P., Jurkovic, M., Kappes, A., Karg, T., Karle, A., Katz, U., Kauer, M., Keivani, A., Kelley, J. L., Kemp, J., Kheirandish, A., Kim, M., Kintscher, T., Kiryluk, J., Klein, S. R., Kohnen, G., Koirala, R., Kolanoski, H., Konietz, R., K��pke, L., Kopper, C., Kopper, S., Koskinen, D. J., Kowalski, M., Krings, K., Kroll, M., Kr��ckl, G., Kr��ger, C., Kunnen, J., Kunwar, S., Kurahashi, N., Kuwabara, T., Labare, M., Lanfranchi, J. L., Larson, M. J., Lennarz, D., Lesiak-Bzdak, M., Leuermann, M., Leuner, J., Lu, L., L��nemann, J., Madsen, J., Maggi, G., Mahn, K. B. M., Mancina, S., Mandelartz, M., Maruyama, R., Mase, K., Matis, H. S., Maunu, R., McNally, F., Meagher, K., Medici, M., Meier, M., Meli, A., Menne, T., Merino, G., Meures, T., Miarecki, S., Middell, E., Mohrmann, L., Montaruli, T., Moulai, M., Nahnhauer, R., Naumann, U., Neer, G., Niederhausen, H., Nowicki, S. C., Nygren, D. R., Pollmann, A. Obertacke, Olivas, A., Omairat, A., O'Murchadha, A., Palczewski, T., Pandya, H., Pankova, D. V., Penek, ��., Pepper, J. A., Heros, C. P��rez de los, Pfendner, C., Pieloth, D., Pinat, E., Posselt, J., Price, P. B., Przybylski, G. T., Quinnan, M., Raab, C., R��del, L., Rameez, M., Rawlins, K., Reimann, R., Relich, M., Resconi, E., Rhode, W., Richman, M., Riedel, B., Robertson, S., Rongen, M., Rott, C., Ruhe, T., Ryckbosch, D., Rysewyk, D., Sabbatini, L., Sandrock, A., Sandroos, J., Sarkar, S., Satalecka, K., Schimp, M., Schlunder, P., Schmidt, T., Schoenen, S., Sch��neberg, S., Sch��nwald, A., Schumacher, L., Seckel, D., Seunarine, S., Soldin, D., Song, M., Spiczak, G. M., Spiering, C., Stahlberg, M., Stamatikos, M., Stanev, T., Stasik, A., Steuer, A., Stezelberger, T., Stokstad, R. G., St��l, A., Str��m, R., Strotjohann, N. L., Sullivan, G. W., Sutherland, M., Taavola, H., Taboada, I., Tatar, J., Ter-Antonyan, S., Terliuk, A., Te��i��, G., Tilav, S., Toale, P. A., Tobin, M. N., Toscano, S., Tosi, D., Tselengidou, M., Turcati, A., Unger, E., Usner, M., Vallecorsa, S., Vandenbroucke, J., van Eijndhoven, N., Vanheule, S., van Rossem, M., van Santen, J., Veenkamp, J., Vehring, M., Voge, M., Vraeghe, M., Walck, C., Wallace, A., Wallraff, M., Wandkowsky, N., Weaver, Ch., Wendt, C., Westerhoff, S., Whelan, B. J., Whitehorn, N., Wickmann, S., Wiebe, K., Wiebusch, C. H., Wille, L., Williams, D. R., Wills, L., Wissing, H., Wolf, M., Wood, T. R., Woschnagg, K., Xu, D. L., Xu, X. W., Xu, Y., Yanez, J. P., Yodh, G., Yoshida, S., Zoll, M., Physics, Elementary Particle Physics, and Faculty of Sciences and Bioengineering Sciences
Subjects: ASTROPHYSICS, Point source, media_common.quotation_subject, Ciencias Físicas, Astrophysics::High Energy Astrophysical Phenomena, NEUTRINO ASTRONOMY, FOS: Physical sciences, Astrophysics, 01 natural sciences, IceCube, purl.org/becyt/ford/1 [https], 0103 physical sciences, Point (geometry), Angular resolution, NEUTRINO TELESCOPE, 010303 astronomy & astrophysics, media_common, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Detector, neutrinos, Astronomy and Astrophysics, purl.org/becyt/ford/1.3 [https], COSMIC-RAYS, astroparticle physics, Space and Planetary Science, Astronomía, GAMMA-RAY, Physics and Astronomy, Neutrino angular resolution, Sky, ddc:520, High Energy Physics::Experiment, Neutrino, Astrophysics - High Energy Astrophysical Phenomena, Event (particle physics), Energy (signal processing), CIENCIAS NATURALES Y EXACTAS
Abstract: Observation of a point source of astrophysical neutrinos would be a "smoking gun" signature of a cosmic-ray accelerator. While IceCube has recently discovered a diffuse flux of astrophysical neutrinos, no localized point source has been observed. Previous IceCube searches for point sources in the southern sky were restricted by either an energy threshold above a few hundred TeV or poor neutrino angular resolution. Here we present a search for southern sky point sources with greatly improved sensitivities to neutrinos with energies below 100 TeV. By selecting charged-current $\nu_{\mu}$ interacting inside the detector, we reduce the atmospheric background while retaining efficiency for astrophysical neutrino-induced events reconstructed with sub-degree angular resolution. The new event sample covers three years of detector data and leads to a factor of ten improvement in sensitivity to point sources emitting below 100 TeV in the southern sky. No statistically significant evidence of point sources was found, and upper limits are set on neutrino emission from individual sources. A posteriori analysis of the highest-energy ~100 TeV starting event in the sample found that this event alone represents a $2.8\sigma$ deviation from the hypothesis that the data consists only of atmospheric background., Comment: 19 pages, 4 figures
Published: 2016

37. Synchronous X-ray and Radio Mode Switches: A Rapid Global Transformation of the Pulsar Magnetosphere

Author: Y. Tang, Anna M. M. Scaife, Steve Rawlings, Aris Karastergiou, Michael W. Wise, Harvey Butcher, B. Ciardi, S. Duscha, V. N. Pandey, Gianni Bernardi, John McKean, Charlotte Sobey, Emanuela Orrú, Chiara Ferrari, M. Kuniyoshi, H. Munk, Marcus Brüggen, Michael Kramer, Cyril Tasse, J. W. Broderick, E. de Geus, Ashish Asgekar, Jason W. T. Hessels, F. de Gasperin, Matthias Hoeft, George Heald, L. Kuiper, A. P. Schoenmakers, P. Maat, R. H. van de Brink, Sera Markoff, Dipanjan Mitra, Philip Best, G. Wright, Ralph A. M. J. Wijers, J. de Plaa, Heino Falcke, V. I. Kondratiev, Rahul Basu, A. Noutsos, T. Coenen, Benjamin Stappers, Michel Tagger, Frank Breitling, Giulia Macario, Rob Fender, Rene C. Vermeulen, Michael R. Bell, F. Batejat, A. Alexov, Marco Iacobelli, H. Paas, Sarod Yatawatta, Patrick Weltevrede, Tim Hassall, R. J. van Weeren, W. Reich, M. Pilia, Laura Birzan, W. Hermsen, Evan Keane, Aleksandar Shulevski, Mark J. Bentum, M. Serylak, Martin Bell, Annalisa Bonafede, J. van Leeuwen, A. Horneffer, Jochen Eislöffel, Maaijke Mevius, H. J. A. Röttgering, A. G. Polatidis, R. Morganti, I. M. Avruch, S. ter Veen, A. W. Gunst, Olaf Wucknitz, Matthias Steinmetz, M. Pandey-Pommier, K. Zagkouris, J. Sluman, Roberto Pizzo, Jean-Mathias Grießmeier, G. Kuper, Philippe Zarka, Joanna M. Rankin, M. A. Garrett, James Miller-Jones, Wilfred Frieswijk, Hermsen, W., Hessels, J.W.T., Kuiper, L., Van Leeuwen, J., Mitra, D., De Plaa, J., Rankin, J.M., Stappers, B.W., Wright, G.A.E., Basu, R., Alexov, A., Coenen, T., Grießmeier, J.-M., Hassall, T.E., Karastergiou, A., Keane, E., Kondratiev, V.I., Kramer, M., Kuniyoshi, M., Noutsos, A., Serylak, M., Pilia, M., Sobey, C., Weltevrede, P., Zagkouris, K., Asgekar, A., Avruch, I.M., Batejat, F., Bell, M.E., Bell, M.R., Bentum, M.J., Bernardi, G., Best, P., Bîrzan, L., Bonafede, A., Breitling, F., Broderick, J., Brüggen, M., Butcher, H.R., Ciardi, B., Duscha, S., Eislöffel, J., Falcke, H., Fender, R., Ferrari, C., Frieswijk, W., Garrett, M.A., De Gasperin, F., De Geus, E., Gunst, A.W., Heald, G., Hoeft, M., Horneffer, A., Iacobelli, M., Kuper, G., Maat, P., Macario, G., Markoff, S., McKean, J.P., Mevius, M., Miller-Jones, J.C.A., Morganti, R., Munk, H., Orrú, E., Paas, H., Pandey-Pommier, M., Pandey, V.N., Pizzo, R., Polatidis, A.G., Rawlings, S., Reich, W., Röttgering, H., Scaife, A.M.M., Schoenmakers, A., Shulevski, A., Sluman, J., Steinmetz, M., Tagger, M., Tang, Y., Tasse, C., Ter Veen, S., Vermeulen, R., Van De Brink, R.H., Van Weeren, R.J., Wijers, R.A.M.J., Wise, M.W., Wucknitz, O., Yatawatta, S., Zarka, P., SRON Netherlands Institute for Space Research (SRON), University of Amsterdam [Amsterdam] (UvA), National Centre for Radio Astrophysics [Pune] (NCRA), Tata Institute for Fundamental Research (TIFR), University of Vermont [Burlington], Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], Astronomy Centre, University of Sussex, Space Telescope Science Institute (STSci), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Oxford Astrophysics, University of Oxford, Centre for Astrophysics and Supercomputing, Swinburne University of Technology [Melbourne], Netherlands Institute for Radio Astronomy (ASTRON), Max-Planck-Institut für Radioastronomie (MPIFR), Onsala Space Observatory (OSO), Chalmers University of Technology [Göteborg], University of Southampton, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, University of Edinburgh, Leiden Observatory [Leiden], Universiteit Leiden, Jacobs University [Bremen], Leibniz-Institut für Astrophysik Potsdam (AIP), Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Thüringer Landessternwarte Tautenburg (TLS), Radboud University [Nijmegen], Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Hamburger Sternwarte/Hamburg Observatory, Universität Hamburg (UHH), Medstar Research Institute, Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], Center for Information Technology CIT, Université de Groningen, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), National Radio Astronomy Observatory [Charlottesville] (NRAO), National Radio Astronomy Observatory (NRAO), School of Physics and Astronomy [Southampton], SKA South Africa, Ska South Africa, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Argelander-Institut für Astronomie (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, ANR-09-JCJC-0001,OPALES(2009), Kapteyn Astronomical Institute, Astronomy, Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), University of Oxford [Oxford], Harvard University [Cambridge]-Smithsonian Institution, Universiteit Leiden [Leiden], Radboud university [Nijmegen], Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: Electromagnetic field, POLARIZATION, Electromagnetic spectrum, Astrophysics::High Energy Astrophysical Phenomena, Astronomy, FOS: Physical sciences, Magnetosphere, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, EMPIRICAL-THEORY, 01 natural sciences, Binary pulsar, Pulsar, Millisecond pulsar, 0103 physical sciences, 010306 general physics, XMM-NEWTON OBSERVATIONS, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, DRIFTING SUBPULSES, Multidisciplinary, B0943+10, Polarization (waves), GAMMA-RAY, [SDU]Sciences of the Universe [physics], 13. Climate action, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, RADIATION, EMISSION, Astrophysics - High Energy Astrophysical Phenomena, PHOTON IMAGING CAMERA, POWERED PULSARS, Radio wave
Abstract: Pulsars emit low-frequency radio waves through to high-energy gamma-rays that are generated anywhere from the surface out to the edges of the magnetosphere. Detecting correlated mode changes in the multi-wavelength emission is therefore key to understanding the physical relationship between these emission sites. Through simultaneous observations, we have detected synchronous switching in the radio and X-ray emission properties of PSR B0943+10. When the pulsar is in a sustained radio 'bright' mode, the X-rays show only an un-pulsed, non-thermal component. Conversely, when the pulsar is in a radio 'quiet' mode, the X-ray luminosity more than doubles and a 100%-pulsed thermal component is observed along with the non-thermal component. This indicates rapid, global changes to the conditions in the magnetosphere, which challenge all proposed pulsar emission theories., Paper published in Science including supplementary material
Published: 2013

38. Gamma ray sources observation with the ARGO-YBJ detector

Author: Aielli G, Bacci C, Bartoli B, Bernardini P, Bi XJ, Bleve C, Branchini P, Budano A, Calabrese Melcarne AK, Camarri P, Cao Z, Cappa A, Cardarelli R, Catalanotti S, Cattaneo C, Celio P, Chen SZ, Chen TL, Chen Y, Cheng N, Creti P, Cui SW, Dai BZ, D'Ali Staiti G, Danzengluobu, Dattoli M, De Mitri I, D'Ettorre Piazzoli B, DE VINCENZI, Mario, Di Girolamo T, Ding XH, Di Sciascio G, Feng CF, Feng Zhao Yang, Feng Zhen Yong, Galeazzi F, Galeotti P, Gargana R, Gou QB, Guo YQ, He HH, Hu Haibing, Hu Hong Bo, Huang Q, Iacovacci M, Iuppa R, James I, Jia HY, Labaciren, Li HJ, Li JY, Li XX, Liberti B, Liguori G, Liu C, Liu CQ, Liu MY, Liu J, Lu H, Ma XH, Mancarella G, Marsella G, Martello D, Mastroianni S, Meng XR, Montini P, Ning CC, Pagliaro A, Panareo M, Perrone L, Pistilli P, Qu XB, Rossi E, Ruggieri F, Saggese L, Salvini P, Santonico R, Shen PR, Sheng XD, Shi F, Stanescu C, Surdo A, Tan YH, Vallania P, Vernetto S, Vigorito C, Wang B, Wang H, Wu CY, Wu HR, Xu B, Xue L, Yan YX, Yang QY, Yang XC, Yuan AF, Zha M, Zhang HM, Zhang Ji Long, Zhang Jian Li, Zhang L, Zhang P, Zhang XY, Zhang Y, Zhaxisangzhu, Zhou XX, Zhu FR, Zhu QQ, Zizzi G., BUSSINO, Severino Angelo Maria, MARI, Stefano Maria, B. Bartoli, BERNARDINI, Paolo, X. J. Bi, C. Bleve, I. Bolognino, P. Branchini, A. Budano, A. K. Calabrese Melcarne, P. Camarri, Z. Cao, A. Cappa, R. Cardarelli, S. Catalanotti, C. Cattaneo, P. Celio, S. Z. Chen, T. L. Chen, Y. Chen, P. Creti, S. W. Cui, B. Z. Dai, G. D’Alì Staiti, Danzengluobu, M. Dattoli, DE MITRI, Ivan, B. D’Ettorre Piazzoli, T. Di Girolamo, X. H. Ding, G. Di Sciascio, C. F. Feng, Zhaoyang Feng, Zhenyong Feng, F. Galeazzi, P. Galeotti, E. Giroletti, Q. B. Gou, Y. Q. Guo, H. H. He, Haibing Huo, Hongbo Hue, Q. Huang, M. Iacovacci, R. Iuppa, I. Jame, H. Y. Jia, Labaciren, H. J. Li, J. Y. Li, X. X. Li, G. Liguori, C. Liu, C. Q. Liu, J. Liu, M. Y. Liu, H. Lu, X. H. Ma, MANCARELLA, Giovanni, S. M. Mari, MARSELLA, GIOVANNI, MARTELLO, Daniele, S. Mastroianni, P. Montini, C. C. Ning, A. Pagliaro, PANAREO, Marco, B. Panico, PERRONE, Lorenzo, P. Pistilli, X. B. Qu, E. Rossi, F. Ruggieri, P. Salvini, R. Santonico, P. R. Shen, X. D. Sheng, F. Shi, C. Stanescu, A. Surdo, Y. H. Tan, P. Vallania, S. Vernetto, C. Vigorito, B. Wang, H. Wang, C. Y. Wu, H. R. Wu, B. Xu, L. Xue, Y. X. Yan, Q. Y. Yang, X. C. Yang, Z. G. Yao, A. F. Yuan, M. Zha, H. M. Zhang, JilongZhang, JianliZhang, L. Zhang, P. Zhang, X. Y. Zhang, Y. Zhang, Zhaxiciren, Zhaxisangzhu, X. X. Zhou, F. R. Zhu, Q. Q. Zhu, G. Zizzi, Aielli, G, Bacci, C, Bartoli, B, Bernardini, P, Bi, Xj, Bleve, C, Branchini, P, Budano, A, Bussino, Severino Angelo Maria, Calabrese Melcarne, Ak, Camarri, P, Cao, Z, Cappa, A, Cardarelli, R, Catalanotti, S, Cattaneo, C, Celio, P, Chen, Sz, Chen, Tl, Chen, Y, Cheng, N, Creti, P, Cui, Sw, Dai, Bz, D'Ali Staiti, G, Dattoli, M, De Mitri, I, D'Ettorre Piazzoli, B, DE VINCENZI, Mario, Di Girolamo, T, Ding, Xh, Di Sciascio, G, Feng, Cf, Feng Zhao, Yang, Feng Zhen, Yong, Galeazzi, F, Galeotti, P, Gargana, R, Gou, Qb, Guo, Yq, He, Hh, Hu, Haibing, Hu Hong, Bo, Huang, Q, Iacovacci, M, Iuppa, R, James, I, Jia, Hy, Li, Hj, Li, Jy, Li, Xx, Liberti, B, Liguori, G, Liu, C, Liu, Cq, Liu, My, Liu, J, Lu, H, Ma, Xh, Mancarella, G, Mari, Stefano Maria, Marsella, G, Martello, D, Mastroianni, S, Meng, Xr, Montini, P, Ning, Cc, Pagliaro, A, Panareo, M, Perrone, L, Pistilli, P, Qu, Xb, Rossi, E, Ruggieri, F, Saggese, L, Salvini, P, Santonico, R, Shen, Pr, Sheng, Xd, Shi, F, Stanescu, C, Surdo, A, Tan, Yh, Vallania, P, Vernetto, S, Vigorito, C, Wang, B, Wang, H, Wu, Cy, Wu, Hr, Xu, B, Xue, L, Yan, Yx, Yang, Qy, Yang, Xc, Yuan, Af, Zha, M, Zhang, Hm, Zhang Ji, Long, Zhang Jian, Li, Zhang, L, Zhang, P, Zhang, Xy, Zhang, Y, Zhaxisangzhu, Zhou, Xx, Zhu, Fr, Zhu, Qq, Zizzi, G., B., Bartoli, Bernardini, Paolo, X. J., Bi, C., Bleve, I., Bolognino, P., Branchini, A., Budano, A. K., Calabrese Melcarne, P., Camarri, Z., Cao, A., Cappa, R., Cardarelli, S., Catalanotti, C., Cattaneo, P., Celio, S. Z., Chen, T. L., Chen, Y., Chen, P., Creti, S. W., Cui, B. Z., Dai, G., D’Alì Staiti, M., Dattoli, B., D’Ettorre Piazzoli, T., Di Girolamo, X. H., Ding, G., Di Sciascio, C. F., Feng, Zhaoyang, Feng, Zhenyong, Feng, F., Galeazzi, P., Galeotti, E., Giroletti, Q. B., Gou, Y. Q., Guo, H. H., He, Haibing, Huo, Hongbo, Hue, Q., Huang, M., Iacovacci, R., Iuppa, I., Jame, H. Y., Jia, H. J., Li, J. Y., Li, X. X., Li, G., Liguori, C., Liu, C. Q., Liu, J., Liu, M. Y., Liu, H., Lu, X. H., Ma, Mancarella, Giovanni, S. M., Mari, Marsella, Giovanni, Martello, Daniele, S., Mastroianni, P., Montini, C. C., Ning, A., Pagliaro, Panareo, Marco, B., Panico, Perrone, Lorenzo, P., Pistilli, X. B., Qu, E., Rossi, F., Ruggieri, P., Salvini, R., Santonico, P. R., Shen, X. D., Sheng, F., Shi, C., Stanescu, A., Surdo, Y. H., Tan, P., Vallania, S., Vernetto, C., Vigorito, B., Wang, H., Wang, C. Y., Wu, H. R., Wu, B., Xu, L., Xue, Y. X., Yan, Q. Y., Yang, X. C., Yang, Z. G., Yao, A. F., Yuan, M., Zha, H. M., Zhang, Jilongzhang, Jianlizhang, L., Zhang, P., Zhang, X. Y., Zhang, Y., Zhang, X. X., Zhou, F. R., Zhu, Q. Q., Zhu, and G., Zizzi
Subjects: Physics, Nuclear and High Energy Physics, Gamma Astronomy, Physics and Astronomy (miscellaneous), Astrophysics::High Energy Astrophysical Phenomena, Detector, Gamma ray, Flux, Astronomy, Extensive Air Shower, Astronomy and Astrophysics, Astrophysics, Gamma-ray astronomy, Array Detector, Gamma-Ray, Argo-Ybj, Gamma Astronomy, Array Detector, Crab Nebula, Air shower, Pulsar, Milagro, Blazar, Instrumentation, Argo
Abstract: In this paper we report on the observations of TeV gamma ray sources performed by the air shower de- tector ARGO-YBJ. The objects studied in this work are the blazar Markarian 421 and the extended galactic source MGROJ1908+06, monitored during 2 years of operation. Mrk421 has been detected by ARGO-YBJ with a statisti- cal significance of 11 standard deviations. The observed TeV emission was highly variable, showing large enhance- ments of the flux during active periods. The study of the spectral behaviour during flares revealed a positive correla- tion of the hardness with the flux, as already reported in the past by the Whipple telescope, suggesting that this is a long term property of the source. ARGO-YBJ observed a strong correlation between TeV gamma rays and the X-ray flux measured by RXTM/ASM and SWIFT/BAT during the whole period, with a time lag compatible with zero, supporting the one-zone SSC model to describe the emission mechanism. MGROJ1908+06 has been detected by ARGO-YBJ with 5 standard deviation of significance. From our data the source appears extended and the measured extension is ext=0.48 +0.26 0.28 , in agreement with a previous HESS obser- vation. The average flux is in marginal agreement with that reported by MILAGRO, but significantly higher than that ob- tained by HESS, suggesting a possible flux variability. The large field of view ( 2 sr) and the high duty cycle allow a continuous monitoring of the sky in the declination band from 0 to 70 . In this paper we report on the ob- servations of two bright gamma ray sources, performed dur- ing 2 years: the blazar Mrk421 and the extended galactic source MGROJ1908+06.
Published: 2012

39. Discovery of Powerful Gamma-Ray Flares from the Crab Nebula

Author: F. Fuschino, Craig O. Heinke, M. Pilia, A. Argan, G. Di Cocco, P. Giommi, Francesco Longo, Fulvio Gianotti, Andrea Bulgarelli, C. Pittori, A. Zambra, Enrico Costa, Guido Barbiellini, Dieter Horns, Carlo Ferrigno, V. Vittorini, M. Trifoglio, Riccardo Campana, M. Prest, Ennio Morelli, E. Striani, F. Perotti, G. Piano, Y. Evangelista, Paolo Lipari, P. Santolamazza, T. Contessi, M. Giusti, Francesco Lazzarotto, Giovanni F. Bignami, Alda Rubini, P. W. Cattaneo, Arnaud Ferrari, D. Zanello, I. Lapshov, Marco Tavani, S. Sabatini, Claudio Labanti, Alessio Trois, Marco Feroci, Luigi Pacciani, Martino Marisaldi, A. De Luca, A. W. Chen, F. Lucarelli, E. Del Monte, L. Salotti, P. A. Caraveo, A. Pellizzoni, A. Morselli, G. DeParis, Martin C. Weisskopf, Allyn F. Tennant, Elena Moretti, M. Galli, P. Picozza, A. Giuliani, A. Rappoldi, E. Vallazza, Sandro Mereghetti, G. Pucella, Massimo Rapisarda, F. Verrecchia, I. Donnarumma, G. Di Persio, Filippo D'Ammando, Paolo Soffitta, S. Vercellone, Tavani, M., Bulgarelli, A., Vittorini, V., Pellizzoni, A., Striani, E., Caraveo, P., Weisskopf, M. C., Tennant, A., Pucella, G., Trois, A., Costa, E., Evangelista, Y., Pittori, C., Verrecchia, F., Del Monte, E., Campana, R., Pilia, M., De Luca, A., Donnarumma, I., Horns, D., Ferrigno, C., Heinke, C. O., Trifoglio, M., Gianotti, F., Vercellone, S., Argan, A., Barbiellini, G., Cattaneo, P. W., Chen, A. W., Contessi, T., D'Ammando, F., Deparis, G., Di Cocco, G., Di Persio, G., Feroci, M., Ferrari, A., Galli, M., Giuliani, A., Giusti, M., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Longo, Francesco, Fuschino, F., Marisaldi, M., Mereghetti, S., Morelli, E., Moretti, E., Morselli, A., Pacciani, L., Perotti, F., Piano, G., Picozza, P., Prest, M., Rapisarda, M., Rappoldi, A., Rubini, A., Sabatini, S., Soffitta, P., Vallazza, E., Zambra, A., Zanello, D., Lucarelli, F., Santolamazza, P., Giommi, P., Salotti, L., Bignami, G. F., Tavani M, Bulgarelli A, Vittorini V, Pellizzoni A, Striani E, Caraveo P, Weisskopf MC, Tennant A, Pucella G, Trois A, Costa E, Evangelista Y, Pittori C, Verrecchia F, Del Monte E, Campana R, Pilia M, De Luca A, Donnarumma I, Horns D, Ferrigno C, Heinke CO, Trifoglio M, Gianotti F, Vercellone S, Argan A, Barbiellini G, Cattaneo PW, Chen AW, Contessi T, DAmmando F, DeParis G, Di Cocco G, Di Persio G, Feroci M, Ferrari A, Galli M, Giuliani A, Giusti M, Labanti C, Lapshov I, Lazzarotto F, Lipari P, Longo F, Fuschino F, Marisaldi M, Mereghetti S, Morelli E, Moretti E, Morselli A, Pacciani L, Perotti F, Piano G, Picozza P, Prest M, Rapisarda M, Rappoldi A, Rubini A, Sabatini S, Soffitta P, Vallazza E, Zambra A, Zanello D, Lucarelli F, Santolamazza P, Giommi P, Salotti L, and Bignami GF
Subjects: individual: Crab Nebula [pulsars], AGILE, Crab Nebula, pulsar, gamma-ray, flare, pulsars: individual: Crab Nebula, High Energy Gamma-ray Astronomy, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Gamma-Ray Flare, gamma-rays, Crab Nebula, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Protoplanetary nebula, Luminosity, law.invention, Emission nebula, Pulsar, law, Astrophysics::Solar and Stellar Astrophysics, Supernova remnant, Astrophysics::Galaxy Astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Nebula, Multidisciplinary, Astronomy, Physics::Space Physics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Flare
Abstract: The well known Crab Nebula is at the center of the SN1054 supernova remnant. It consists of a rotationally-powered pulsar interacting with a surrounding nebula through a relativistic particle wind. The emissions originating from the pulsar and nebula have been considered to be essentially stable. Here we report the detection of strong gamma-ray (100 MeV-10 GeV) flares observed by the AGILE satellite in September, 2010 and October, 2007. In both cases, the unpulsed flux increased by a factor of 3 compared to the non-flaring flux. The flare luminosity and short timescale favor an origin near the pulsar, and we discuss Chandra Observatory X-ray and HST optical follow-up observations of the nebula. Our observations challenge standard models of nebular emission and require power-law acceleration by shock-driven plasma wave turbulence within a ~1-day timescale., Comment: 23 pages (including Supporting On-line Material), 8 figures, 1 table. Version published in Science Express on January 6, 2011 (available at http://www.sciencemag.org/content/early/2011/01/05/science.1200083)
Published: 2011

40. Design and initial tests of the Tracker-converter of the Gamma-ray Large Area Space Telescope

Author: N. Kawai, Carmelo Sgrò, Luca Baldini, M. Hirayama, M. Razzano, M. Ozaki, G. Scolieri, M. Kuss, H. Tajima, M. Sugizaki, A. De Angelis, D. Nelson, C. Cecchi, M. N. Mazziotta, Hartmut Sadrozinski, Hiromitsu Takahashi, C. Young, M. Nordby, S. Rainò, S. Yoshida, Alessandro Brez, Francesco Longo, Johann Cohen-Tanugi, D. Rich, R. Giannitrapani, P. Spinelli, P. Fusco, W. B. Atwood, Robert R. Rando, T. Borden, F. Belli, Nicola Giglietto, W. Kroeger, M. Brigida, G.A. Caliandro, P. Lubrano, M.M. Massai, Francesco Giordano, M. Pepe, M. Ziegler, F. Loparco, Persis S. Drell, T. Himel, A. Morselli, Massimo Minuti, S. Germani, C. Favuzzi, Guido Barbiellini, Jun Kataoka, Ronaldo Bellazzini, Gloria Spandre, F. Gargano, Luca Latronico, Nicola Omodei, Tadayuki Takahashi, Hideaki Katagiri, Tsunefumi Mizuno, R. P. Johnson, Yasushi Fukazawa, R. Bagagli, T. Ohsugi, ATWOOD W., B, Bagagli, R, Baldini, L, Bellazzini, R, BARBIELLINI AMIDEI, Guido, Belli, F, Borden, T, Brez, A, Brigida, M, CALIANDRO G., A, Cecchi, C, COHEN TANUGI, J, DE ANGELIS, A, Drell, P, Favuzzi, C, Fukazawa, Y, Fusco, P, Gargano, F, Germani, S, Giannitrapani, R, Giglietto, N, Giordano, F, Himel, T, Hirayama, M, JOHNSON R., P, Katagiri, H, Kataoka, J, Kawai, N, Kroeger, W, Kuss, M, Latronico, L, Longo, Francesco, Loparco, F, Lubrano, P, MASSAI M., M, MAZZIOTTA M., N, Minuti, M, Mizuno, T, Morselli, A, Nelson, D, Nordby, M, Ohsugi, T, Omodei, N, Ozaki, M, Pepe, M, Rainò, S, Rando, R, Razzano, M, Rich, D, SADROZINSKI H. F., W, Scolieri, G, Sgrò, C, Spandre, G, Spinelli, P, Sugizaki, M, Tajima, H, Takahashi, H, Takahashi, T, Yoshida, S, Young, C, and Ziegler, M.
Subjects: Physics, Physics::Instrumentation and Detectors, business.industry, Passive cooling, Astrophysics::High Energy Astrophysical Phenomena, Track (disk drive), Detector, Electrical engineering, Astronomy and Astrophysics, Astrophysics, telescope, tracking, Modular design, Tracking (particle physics), Gamma-ray, law.invention, Telescope, Spitzer Space Telescope, law, Electronics, business
Abstract: 著者人数: 61名, Accepted: 2007-08-22, 資料番号: SA1000711000
Published: 2007

41. Atmospheric and astrophysical neutrinos above 1 TeV interacting in IceCube

Author: K. Hoshina, Glenn Spiczak, Markus Ahlers, Albrecht Karle, U. Naumann, Mohamed Rameez, E. Unger, A. Schönwald, Gerald Przybylski, M. Zoll, D. Altmann, K. Meagher, Samvel Ter-Antonyan, M. Relich, L. Schulte, Christian Bohm, Aongus O'Murchadha, Benedikt Riedel, K. Rawlins, Christian Spiering, B. J. Whelan, G. C. Hill, M. Quinnan, J. C. Díaz-Vélez, A. Stasik, J. van Santen, James Madsen, Segev BenZvi, K. Clark, Gary Binder, Axel Groß, K. Frantzen, L. Gladstone, D. Heereman, Joakim Sandroos, Azadeh Keivani, F. Clevermann, Y. Sestayo, Justin Vandenbroucke, J. P. Yanez, Dirk Heinen, E. A. Strahler, D. Seckel, S. Miarecki, A. R. Fazely, J. Blumenthal, M. Kowalski, Thomas Meures, M. N. Tobin, Tyce DeYoung, P. A. Toale, Tim Ruhe, M. Danninger, L. Mohrmann, O. Schulz, D. Berley, R. Nahnhauer, P. B. Price, A. Koob, Timo Karg, E. Jacobi, Spencer Klein, Hermann Kolanoski, J. Pütz, Matthias Vraeghe, P. O. Hulth, J. Eisch, Olga Botner, Teresa Montaruli, A. Christov, Björn Eichmann, A. Franckowiak, J. Miller, T. O. B. Schmidt, N. L. Strotjohann, D. Z. Besson, A. Kriesten, V. Baum, Aya Ishihara, T. Feusels, J. P. A. M. de André, C. Walck, H.-P. Bretz, Juanan Aguilar, J.-H. Köhne, H. Wissing, T. R. Wood, Kara Hoffman, A. H. Cruz Silva, P. Gretskov, B. Christy, Kurt Woschnagg, K. Krings, Chris Wendt, Frank McNally, Carl Pfendner, J. E. Jacobsen, Marcos Santander, H. S. Matis, Daniel Bindig, J. Felde, Xinhua Bai, Paul Evenson, J. P. Rodrigues, T. C. Arlen, T. Stezelberger, S. M. Saba, M. Casier, J. Auffenberg, A. Obertacke, K. Mase, A. Homeier, Nathan Whitehorn, Ch. Weaver, Christopher Wiebusch, J. Daughhetee, Wolfgang Rhode, A. Meli, J. L. Kelley, M. Leuermann, F. Bos, N. Buzinsky, A. Terliuk, S. Westerhoff, Dmitry Chirkin, M. Jurkovic, M. Kauer, Allan Hallgren, Delia Tosi, R. Hellauer, S. Seunarine, Chad Finley, Sandro Kopper, R. C. Bay, L. Gerhardt, C. Haack, Carlos Arguelles, E. Pinat, D. Hellwig, Mike Richman, Alexander Kappes, K. Schatto, G. Kohnen, S. Zierke, Sally Robertson, Dennis Soldin, Rezo Shanidze, J. J. Beatty, Donglian Xu, A. Omairat, M. G. Aartsen, H. Taavola, Anatoli Fedynitch, S. Hussain, D. J. Koskinen, Maria Tselengidou, Ö. Penek, Francis Halzen, S. Schöneberg, P. Zarzhitsky, L. Rädel, E. Blaufuss, P. Hallen, N. A. Stanisha, M. Kroll, M. Schmitz, K. Jero, Darren Grant, D. J. Boersma, J. C. Davis, K. Jagielski, J. Casey, Jay Gallagher, René Reimann, R. Morse, K. D. de Vries, M. J. Larson, Matthias Wolf, Sarah Nowicki, O. Fadiran, B. Ruzybayev, T. Anderson, J. Posselt, Subir Sarkar, M. Lesiak-Bzdak, P. Redl, G. Tešić, G. W. Sullivan, A. Stößl, Sofia Vallecorsa, A. Tamburro, A. Olivas, Reina H. Maruyama, R. Ström, M. Vehring, D. F. Cowen, Klas Hultqvist, J. Kiryluk, Kirill Filimonov, R. Maunu, T. Kuwabara, S. De Ridder, C. Ha, P. Berghaus, J. Kläs, D. Gier, M. Labare, F. Huang, J. Kunnen, H. G. Sander, D. Bose, Damian Pieloth, Ali Kheirandish, A. M. Brown, Maryon Ahrens, T. Fuchs, T. Palczewski, M. Medici, S. Coenders, L. Köpke, J. C. Groh, C. Wichary, C. Kopper, B. Eberhardt, O. Jlelati, S. Tilav, Ignacio Taboada, M. Stamatikos, A. Goldschmidt, K.-H. Becker, Matt Dunkman, T. Fischer-Wasels, A. Schukraft, E. Cheung, Dirk Ryckbosch, N. Milke, George Japaridze, S. Euler, Jenni Adams, Kael Hanson, R. Gaior, Steven W. Barwick, N. Kurahashi, Todor Stanev, Dawn Williams, Paolo Desiati, N. van Eijndhoven, Elisa Resconi, E. Middlemas, G. Kroll, D. T. Larsen, S. Yoshida, S. Hickford, R. Hoffmann, R. Eagan, R. G. Stokstad, Thomas K. Gaisser, G. B. Yodh, Javier Gonzalez, Giorgio Maggi, C. De Clercq, S. Böser, I. Rees, J. Feintzeig, Markus Ackermann, J. Lünemann, J. A. Goodman, G. Golup, M. Wellons, Dariusz Gora, Joshua Pepper, J. Becker Tjus, E. Middell, Elisa Bernardini, B. Kaminsky, C. Pérez de los Heros, K. Wiebe, L. Classen, M. W. E. Smith, S. Schoenen, Thorsten Glusenkamp, L. Brayeur, Dustin Hebecker, S. Flis, W. Huelsnitz, Carsten Rott, Dave Nygren, M. Bissok, Xianwu Xu, K. Helbing, J. Ziemann, M. Day, A. Haj Ismail, M. Usner, Martin Rongen, Hans Niederhausen, S. Odrowski, M. Wallraff, M. Voge, A. Bernhard, A. Tepe, J. Leute, Larissa Paul, F. Scheriau, Physics, and Elementary Particle Physics
Subjects: HIGH-ENERGY NEUTRINOS, Nuclear and High Energy Physics, Particle physics, AMANDA, Meson, Solar neutrino, Astrophysics::High Energy Astrophysical Phenomena, INDUCED CASCADES, FOS: Physical sciences, Cosmic ray, Astrophysics, FLUX PREDICTIONS, 01 natural sciences, IceCube Neutrino Observatory, IceCube, Observatory, SEARCH, 0103 physical sciences, ddc:530, Blazar, 010303 astronomy & astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Astrophysics::Instrumentation and Methods for Astrophysics, ASTRONOMY, PERFORMANCE, BLAZARS, PROMPT LEPTONS, GAMMA-RAY, Physics and Astronomy, High Energy Physics::Experiment, Neutrino astronomy, Neutrino, Astrophysics - High Energy Astrophysical Phenomena, physics
Abstract: The IceCube Neutrino Observatory was designed primarily to search for high-energy (TeV--PeV) neutrinos produced in distant astrophysical objects. A search for $\gtrsim 100$~TeV neutrinos interacting inside the instrumented volume has recently provided evidence for an isotropic flux of such neutrinos. At lower energies, IceCube collects large numbers of neutrinos from the weak decays of mesons in cosmic-ray air showers. Here we present the results of a search for neutrino interactions inside IceCube's instrumented volume between 1~TeV and 1~PeV in 641 days of data taken from 2010--2012, lowering the energy threshold for neutrinos from the southern sky below 10 TeV for the first time, far below the threshold of the previous high-energy analysis. Astrophysical neutrinos remain the dominant component in the southern sky down to 10 TeV. From these data we derive new constraints on the diffuse astrophysical neutrino spectrum, $\Phi_{\nu} = 2.06^{+0.4}_{-0.3} \times 10^{-18} \left({E_{\nu}}/{10^5 \,\, \rm{GeV}} \right)^{-2.46 \pm 0.12} {\rm {GeV^{-1} \, cm^{-2} \, sr^{-1} \, s^{-1}} } $, as well as the strongest upper limit yet on the flux of neutrinos from charmed-meson decay in the atmosphere, 1.52 times the benchmark theoretical prediction used in previous IceCube results at 90\% confidence., Comment: 18 pages, 12 figures
Published: 2015

42. Dark matter constraints from observations of 25 Milky Way satellite galaxies with the Fermi Large Area Telescope

Author: Fermi-LAT Collaboration, Ackermann, Markus, Bissaldi, E., Sgrò, C., Siskind, E. J., Spinelli, P., Strigari, L., Suson, D. J., Tajima, H., Takahashi, H., Thayer, J. B., Tibaldo, L., Tinivella, M., Bloom, E. D., Torres, D. F., Uchiyama, Y., Usher, T. L., Vandenbroucke, J., Vianello, G., Vitale, V., Werner, M., Winer, B. L., Wood, K. S., Wood, M., Bonamente, E., Zaharijas, G., Zimmer, S., Bouvier, A., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Albert, A., Caliandro, G. A., Cameron, R. A., Caragiulo, M., Caraveo, P. A., Cecchi, C., Charles, E., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Anderson, B., Cohen-Tanugi, J., Conrad, J., D'Ammando, F., de Angelis, A., Dermer, C. D., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Essig, R., Baldini, L., Favuzzi, C., Ferrara, E. C., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Giglietto, N., Giroletti, M., Ballet, J., Godfrey, G., Gomez-Vargas, G. A., Grenier, I. A., Guiriec, Gustafsson, M., Hayashida, M., Hays, E., Hewitt, J., Hughes, R. E., Jogler, T., Barbiellini, G., Kamae, T., Knödlseder, J., Kocevski, D., Kuss, M., Larsson, ., Latronico, L., Garde, M. Llena, Longo, F., Loparco, F., Lovellette, M. N., Bastieri, D., Lubrano, P., Martinez, G., Mayer, Michael, Mazziotta, M. N., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monzani, M. E., Morselli, A., Bechtol, K., Moskalenko, I. V., Murgia, S., Nemmen, R., Nuss, E., Ohsugi, T., Orlando, E., Ormes, J. F., Perkins, J. S., Piron, F., Pivato, G., Bellazzini, R., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Ritz, S., Sànchez-Conde, M., Sehgal, N., Ackermann M, Albert A, Anderson B, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Bissaldi E, Bloom ED, Bonamente E, Bouvier A, Brandt TJ, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro GA, Cameron RA, Caragiulo M, Caraveo PA, Cecchi C, Charles E, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, DAmmando F, de Angelis A, Dermer CD, Digel SW, Silva EDE, Drell PS, Drlica-Wagner A, Essig R, Favuzzi C, Ferrara EC, Franckowiak A, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Giglietto N, Giroletti M, Godfrey G, Gomez-Vargas GA, Grenier IA, Guiriec S, Gustafsson M, Hayashida M, Hays E, Hewitt J, Hughes RE, Jogler T, Kamae T, Knodlseder J, Kocevski D, Kuss M, Larsson S, Latronico L, Garde ML, Longo F, Loparco F, Lovellette MN, Lubrano P, Martinez G, Mayer M, Mazziotta MN, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nemmen R, Nuss E, Ohsugi T, Orlando E, Ormes JF, Perkins JS, Piron F, Pivato G, Porter TA, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Ritz S, Sanchez-Conde M, Sehgal N, Sgro C, Siskind EJ, Spinelli P, Strigari L, Suson DJ, Tajima H, Takahashi H, Thayer JB, Tibaldo L, Tinivella M, Torres DF, Uchiyama Y, Usher TL, Vandenbroucke J, Vianello G, Vitale V, Werner M, Winer BL, Wood KS, Wood M, Zaharijas G, Zimmer S, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Particules de Montpellier (LUPM), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Fermi-LAT, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT), Ackermann, M., Albert, A., Anderson, B., Baldini, L., Ballet, J., BARBIELLINI AMIDEI, Guido, Bastieri, D., Bechtol, K., Bellazzini, R., Bissaldi, Elisabetta, Bloom, E. D., Bonamente, E., Bouvier, A., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caragiulo, M., Caraveo, P. A., Cecchi, C., Charles, E., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Cohen Tanugi, J., Conrad, J., D'Ammando, F., De Angelis, A., Dermer, C. D., Digel, S. W., Do Couto E. Silva, E., Drell, P. S., Drlica Wagner, A., Essig, R., Favuzzi, C., Ferrara, E. C., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Giglietto, N., Giroletti, M., Godfrey, G., Gomez Vargas, G. A., Grenier, I. A., Guiriec, S., Gustafsson, M., Hayashida, M., Hays, E., Hewitt, J., Hughes, R. E., Jogler, T., Kamae, T., Knödlseder, J., Kocevski, D., Kuss, M., Larsson, S., Latronico, L., Llena Garde, M., Longo, Francesco, Loparco, F., Lovellette, M. N., Lubrano, P., Martinez, G., Mayer, M., Mazziotta, M. N., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nemmen, R., Nuss, E., Ohsugi, T., Orlando, E., Ormes, J. F., Perkins, J. S., Piron, F., Pivato, G., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Ritz, S., Sánchez Conde, M., Sehgal, N., Sgrò, C., Siskind, E. J., Spinelli, P., Strigari, L., Suson, D. J., Tajima, H., Takahashi, H., Thayer, J. B., Tibaldo, L., Tinivella, M., Torres, D. F., Uchiyama, Y., Usher, T. L., Vandenbroucke, J., Vianello, G., Vitale, V., Werner, M., Winer, B. L., Wood, K. S., Wood, M., Zaharijas, G., and Zimmer, S.
Subjects: 95.85.Pw, Dwarf galaxy problem, Astrophysics, 01 natural sciences, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), Galaxy group, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], gamma-ray, gamma ray: flux, 98.52.Wz, 010303 astronomy & astrophysics, Dwarf galaxies, High Energy Astrophysical Phenomena (astro-ph.HE), [PHYS]Physics [physics], Physics, Hot dark matter, gamma ray: emission, statistics, kinematics, Computer Science::Mathematical Software, Elliptical galaxy, Computer Science::Programming Languages, 95.35.+d, Dark galaxy, Astrophysics - High Energy Astrophysical Phenomena, performance, Dark matter, gamma-ray, Dwarf galaxies, Nuclear and High Energy Physics, WIMP, Astrophysics::High Energy Astrophysical Phenomena, satellite, FOS: Physical sciences, dark matter: density, Astrophysics::Cosmology and Extragalactic Astrophysics, Computer Science::Digital Libraries, gamma ray: energy spectrum, GLAST, cross section: annihilation, S030DMA, 0103 physical sciences, Dark matter, flux: upper limit, ddc:530, Astrophysics::Galaxy Astrophysics, Dwarf galaxy, background, 010308 nuclear & particles physics, Astronomy, dark matter: annihilation, Navarro-Frenk-White profile, Dwarf spheroidal galaxy, Dark matter halo, Automatic Keywords, 13. Climate action, galaxy, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: The dwarf spheroidal satellite galaxies of the Milky Way are some of the most dark-matter-dominated objects known. Due to their proximity, high dark matter content, and lack of astrophysical backgrounds, dwarf spheroidal galaxies are widely considered to be among the most promising targets for the indirect detection of dark matter via gamma rays. Here we report on gamma-ray observations of 25 Milky Way dwarf spheroidal satellite galaxies based on 4 years of Fermi Large Area Telescope (LAT) data. None of the dwarf galaxies are significantly detected in gamma rays, and we present gamma-ray flux upper limits between 500 MeV and 500 GeV. We determine the dark matter content of 18 dwarf spheroidal galaxies from stellar kinematic data and combine LAT observations of 15 dwarf galaxies to constrain the dark matter annihilation cross section. We set some of the tightest constraints to date on the the annihilation of dark matter particles with masses between 2 GeV and 10 TeV into prototypical Standard Model channels. We find these results to be robust against systematic uncertainties in the LAT instrument performance, diffuse gamma-ray background modeling, and assumed dark matter density profile., 47 pages, 8 figure, and 8 tables. Contact authors: Johann Cohen-Tanugi, Jan Conrad, Alex Drlica-Wagner, Maja Llena Garde, and Nicola Mazziotta
Published: 2014

43. Inferred Cosmic-Ray Spectrum from Fermi Large Area Telescope γ-Ray Observations of Earth’s Limb

Author: Ackermann, M, Ajello, M, Albert, A, Allafort, A, Baldini, L, Barbiellini, G, Bastieri, D, Bechtol, K, Bellazzini, R, Blandford, RD, Bloom, ED, Bonamente, E, Bottacini, E, Bouvier, A, Brandt, TJ, Brigida, M, Bruel, P, Buehler, R, Buson, S, Caliandro, GA, Cameron, RA, Caraveo, PA, Cecchi, C, Charles, E, Chaves, RCG, Chekhtman, A, Chiang, J, Chiaro, G, Ciprini, S, Claus, R, Cohen-Tanugi, J, Conrad, J, Cutini, S, Dalton, M, D'Ammando, F, de Angelis, A, de Palma, F, Dermer, CD, Digel, SW, Di Venere, L, do Couto e Silva, E, Drell, PS, Drlica-Wagner, A, Favuzzi, C, Fegan, SJ, Ferrara, EC, Focke, WB, Franckowiak, A, Fukazawa, Y, Funk, S, Fusco, P, Gargano, F, Gasparrini, D, Germani, S, Giglietto, N, Giordano, F, Giroletti, M, Glanzman, T, Godfrey, G, Gomez-Vargas, GA, Grenier, IA, Grove, JE, Guiriec, S, Gustafsson, M, Hadasch, D, Hanabata, Y, Harding, AK, Hayashida, M, Hayashi, K, Hewitt, JW, Horan, D, Hou, X, Hughes, RE, Inoue, Y, Jackson, MS, Jogler, T, Johannesson, G, Johnson, AS, Kamae, T, Kawano, T, Knoedlseder, J, Kuss, M, Lande, J, Larsson, S, Latronico, L, Longo, F, Loparco, F, Lovellette, MN, Lubrano, P, Mayer, M, Mazziotta, MN, McEnery, JE, Mehault, J, Michelson, PF, Mitthumsiri, W, Mizuno, T, Moiseev, AA, Monte, C, Monzani, ME, Morselli, A, Moskalenko, IV, Murgia, S, Nemmen, R, Nuss, E, Ohsugi, T, Okumura, A, Orienti, M, Orlando, E, Ormes, JF, Paneque, D, Panetta, JH, Perkins, JS, Pesce-Rollins, M, Piron, F, Pivato, G, Porter, TA, Raino, S, Rando, R, Razzano, M, Razzaque, S, Reimer, A, Reimer, O, Ritz, S, Roth, M, Schaal, M, Schulz, A, Sgro, C, Siskind, EJ, Spandre, G, Spinelli, P, Strong, AW, Takahashi, H, Takeuchi, Y, Thayer, JG, Thayer, JB, Thompson, DJ, Tibaldo, L, Tinivella, M, Torres, DF, Tosti, G, Troja, E, Tronconi, V, Usher, TL, Vandenbroucke, J, Vasileiou, V, Vianello, G, Vitale, V, Werner, M, Winer, BL, Wood, KS, Wood, M, Yang, Z, Collaboration, LAT, Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Particules de Montpellier (LUPM), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT), Fermi-LAT, Ackermann M, Ajello M, Albert A, Allafort A, Baldini L, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Blandford RD, Bloom ED, Bonamente E, Bottacini E, Bouvier A, Brandt TJ, Brigida M, Bruel P, Buehler R, Buson S, Caliandro GA, Cameron RA, Caraveo PA, Cecchi C, Charles E, Chaves RCG, Chekhtman A, Chiang J, Chiaro G, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, Dalton M, DAmmando F, de Angelis A, de Palma F, Dermer CD, Digel SW, Di Venere L, Silva EDE, Drell PS, Drlica-Wagner A, Favuzzi C, Fegan SJ, Ferrara EC, Focke WB, Franckowiak A, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Gomez-Vargas GA, Grenier IA, Grove JE, Guiriec S, Gustafsson M, Hadasch D, Hanabata Y, Harding AK, Hayashida M, Hayashi K, Hewitt JW, Horan D, Hou X, Hughes RE, Inoue Y, Jackson MS, Jogler T, Johannesson G, Johnson AS, Kamae T, Kawano T, Knodlseder J, Kuss M, Lande J, Larsson S, Latronico L, Longo F, Loparco F, Lovellette MN, Lubrano P, Mayer M, Mazziotta MN, McEnery JE, Mehault J, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nemmen R, Nuss E, Ohsugi T, Okumura A, Orienti M, Orlando E, Ormes JF, Paneque D, Panetta JH, Perkins JS, Pesce-Rollins M, Piron F, Pivato G, Porter TA, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Ritz S, Roth M, Schaal M, Schulz A, Sgro C, Siskind EJ, Spandre G, Spinelli P, Strong AW, Takahashi H, Takeuchi Y, Thayer JG, Thayer JB, Thompson DJ, Tibaldo L, Tinivella M, Torres DF, Tosti G, Troja E, Tronconi V, Usher TL, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Werner M, Winer BL, Wood KS, Wood M, Yang Z, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Ackermann, M, Ajello, M., Albert, A., Allafort, A., Baldini, L., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Blandford, R. D., Bloom, E. D., Bonamente, E., Bottacini, E., Bouvier, A., Brandt, T. J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Cecchi, C., Charles, E., Chaves, R. C. G., Chekhtman, A., Chiang, J., Chiaro, G., Ciprini, S., Claus, R., Cohen Tanugi, J., Conrad, J., Cutini, S., Dalton, M., Dammando, F., De Angelis, A., De Palma, F., Dermer, C. D., Digel, S. W., Di Venere, L., Do Couto E. Silva, E., Drell, P. S., Drlica Wagner, A., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Gomez Vargas, G. A., Grenier, I. A., Grove, J. E., Guiriec, S., Gustafsson, M., Hadasch, D., Hanabata, Y., Harding, A. K., Hayashida, M., Hayashi, K., Hewitt, J. W., Horan, D., Hou, X., Hughes, R. E., Inoue, Y., Jackson, M. S., Jogler, T., Jóhannesson, G., Johnson, A. S., Kamae, T., Kawano, T., Knödlseder, J., Kuss, M., Lande, J., Larsson, S., Latronico, L., Longo, Francesco, Loparco, F., Lovellette, M. N., Lubrano, P., Mayer, M., Mazziotta, M. N., Mcenery, J. E., Mehault, J., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nemmen, R., Nuss, E., Ohsugi, T., Okumura, A., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Perkins, J. S., Pesce Rollins, M., Piron, F., Pivato, G., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Ritz, S., Roth, M., Schaal, M., Schulz, A., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Strong, A. W., Takahashi, H., Takeuchi, Y., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tibaldo, L., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Tronconi, V., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Werner, M., Winer, B. L., Wood, K. S., Wood, M., and Yang, Z.
Subjects: Proton, 95.85.Pw, 95.85.Ry, Astrophysics::High Energy Astrophysical Phenomena, General Physics and Astronomy, Cosmic ray, Astrophysics, Composition energy spectra and interactions, gamma-ray, Neutrino muon pion and other elementary particles, cosmic rays, Cosmic rays, Photon energy, helium: spectrum, Neutrino muon pion and other elementary particles, 01 natural sciences, GLAST, Spectral line, law.invention, 98.70.Sa, Telescope, cosmic rays, PAMELA, law, 0103 physical sciences, ddc:550, gamma-ray, Composition energy spectra and interactions, Nuclear Experiment, 010306 general physics, 010303 astronomy & astrophysics, 96.50.sb, [PHYS]Physics [physics], Physics, cosmic radiation: spectrum, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], p: spectrum, Gamma ray, photon: energy, Galaxy, gamma ray: emission, High Energy Physics::Experiment, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], CREAM, Fermi Gamma-ray Space Telescope
Abstract: 著者人数: 152名, 資料番号: SA1140046000
Published: 2014

44. OBSERVATION AND CHARACTERIZATION OF A COSMIC MUON NEUTRINO FLUX FROM THE NORTHERN HEMISPHERE USING SIX YEARS OF ICECUBE DATA

Author: Aartsen, M. G., Abraham, K., Ansseau, I., Grant, D., Griffith, Z., Haack, C., Ismail, A. Haj, Hallgren, A., Halzen, F., Hansen, E., Hansmann, B., Hansmann, T., Hanson, K., Anton, G., Hebecker, D., Heereman, D., Helbing, K., Hellauer, R., Hickford, S., Hignight, J., Hill, G. C., Hoffman, K. D., Hoffmann, R., Holzapfel, K., Archinger, M., Hoshina, K., Huang, F., Huber, M., Hultqvist, K., In, S., Ishihara, A., Jacobi, E., Japaridze, G. S., Jeong, M., Jero, K., Argüelles, C., Jones, B. J. P., Jurkovic, M., Kappes, A., Karg, T., Karle, A., Katz, U., Kauer, M., Keivani, A., Kelley, J. L., Kemp, J., Auffenberg, J., Kheirandish, A., Kim, M., Kintscher, T., Kiryluk, J., Kittler, T., Klein, S. R., Kohnen, G., Koirala, R., Kolanoski, H., Konietz, R., Axani, S., Köpke, L., Kopper, C., Kopper, S., Koskinen, D. J., Kowalski, M., Krings, K., Kroll, M., Krückl, G., Krüger, C., Kunnen, J., Bai, X., Kunwar, S., Kurahashi, N., Kuwabara, T., Labare, M., Lanfranchi, J. L., Larson, M. J., Lauber, F., Lennarz, D., Lesiak-Bzdak, M., Leuermann, M., Barwick, S. W., Leuner, J., Lu, L., Lünemann, J., Madsen, J., Maggi, G., Mahn, K. B. M., Mancina, S., Mandelartz, M., Maruyama, R., Mase, K., Baum, V., Maunu, R., McNally, F., Meagher, K., Medici, M., Meier, M., Meli, A., Menne, T., Merino, G., Meures, T., Miarecki, S., Bay, R., Mohrmann, L., Montaruli, T., Moulai, M., Nahnhauer, R., Naumann, U., Neer, G., Niederhausen, H., Nowicki, S. C., Nygren, D. R., Pollmann, A. Obertacke, Ackermann, M., Beatty, J. J., Olivas, A., O’Murchadha, A., Palczewski, T., Pandya, H., Pankova, D. V., Peiffer, P., Penek, Ö., Pepper, J. A., Heros, C. Pérez de los, Pieloth, D., Tjus, J. Becker, Pinat, E., Price, P. B., Przybylski, G. T., Quinnan, M., Raab, C., Rädel, L., Rameez, M., Rawlins, K., Reimann, R., Relethford, B., Becker, K.-H., Relich, M., Resconi, E., Rhode, W., Richman, M., Riedel, B., Robertson, S., Rongen, M., Rott, C., Ruhe, T., Ryckbosch, D., BenZvi, S., Rysewyk, D., Sabbatini, L., Herrera, S. E. Sanchez, Sandrock, A., Sandroos, J., Sarkar, S., Satalecka, K., Schimp, M., Schlunder, P., Schmidt, T., Berghaus, P., Schoenen, S., Schöneberg, S., Schumacher, L., Seckel, D., Seunarine, S., Soldin, D., Song, M., Spiczak, G. M., Spiering, C., Stahlberg, M., Berley, D., Stanev, T., Stasik, A., Steuer, A., Stezelberger, T., Stokstad, R. G., Stößl, A., Ström, R., Strotjohann, N. L., Sullivan, G. W., Sutherland, M., Bernardini, E., Taavola, H., Taboada, I., Tatar, J., Tenholt, F., Ter-Antonyan, S., Terliuk, A., Tešić, G., Tilav, S., Toale, P. A., Tobin, M. N., Bernhard, A., Toscano, S., Tosi, D., Tselengidou, M., Turcati, A., Unger, E., Usner, M., Vandenbroucke, J., Eijndhoven, N. van, Vanheule, S., Rossem, M. van, Besson, D. Z., Santen, J. van, Veenkamp, J., Vehring, M., Voge, M., Vraeghe, M., Walck, C., Wallace, A., Wallraff, M., Wandkowsky, N., Weaver, Ch., Binder, G., Weiss, M. J., Wendt, C., Westerhoff, S., Whelan, B. J., Wickmann, S., Wiebe, K., Wiebusch, C. H., Wille, L., Williams, D. R., Wills, L., Adams, J., Bindig, D., Wolf, M., Wood, T. R., Woolsey, E., Woschnagg, K., Xu, D. L., Xu, X. W., Xu, Y., Yanez, J. P., Yodh, G., Yoshida, S., Bissok, M., Zoll, M., IceCube Collaboration, Blaufuss, E., Blot, S., Bohm, C., Börner, M., Bos, F., Bose, D., Böser, S., Botner, O., Aguilar, J. A., Braun, J., Brayeur, L., Bretz, H.-P., Burgman, A., Carver, T., Casier, M., Cheung, E., Chirkin, D., Christov, A., Clark, K., Ahlers, M., Classen, L., Coenders, S., Collin, G. H., Conrad, J. M., Cowen, D. F., Cross, R., Day, M., André, J. P. A. M. de, Clercq, C. De, Rosendo, E. del Pino, Ahrens, M., Dembinski, H., Ridder, S. De, Desiati, P., Vries, K. D. de, Wasseige, G. de, With, M. de, DeYoung, T., Díaz-Vélez, J. C., Lorenzo, V. di, Dujmovic, H., Altmann, D., Dumm, J. P., Dunkman, M., Eberhardt, B., Ehrhardt, T., Eichmann, B., Eller, P., Euler, S., Evenson, P. A., Fahey, S., Fazely, A. R., Andeen, K., Feintzeig, J., Felde, J., Filimonov, K., Finley, C., Flis, S., Fösig, C.-C., Franckowiak, A., Friedman, E., Fuchs, T., Gaisser, T. K., Anderson, T., Gallagher, J., Gerhardt, L., Ghorbani, K., Giang, W., Gladstone, L., Glagla, M., Glüsenkamp, Thorsten, Goldschmidt, A., Golup, G., Gonzalez, J. G., Vriendenkring VUB, Physics, and Elementary Particle Physics
Subjects: ASTROPHYSICS, AMANDA, Particle physics, TELESCOPE, Meson, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, ACCELERATION, 01 natural sciences, astroparticle physics, methods: data analysis, neutrinos, Astronomy and Astrophysics, Space and Planetary Science, RATIO, 0103 physical sciences, data analysis [methods], Muon neutrino, 010303 astronomy & astrophysics, Zenith, Charged current, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Spectral index, Muon, 010308 nuclear & particles physics, Glashow resonance, ASTRONOMY, PERFORMANCE, GAMMA-RAY, LIGHT, Physics and Astronomy, 13. Climate action, ddc:520, High Energy Physics::Experiment, Neutrino, Astrophysics - High Energy Astrophysical Phenomena, SYSTEM
Abstract: The IceCube Collaboration has previously discovered a high-energy astrophysical neutrino flux using neutrino events with interaction vertices contained within the instrumented volume of the IceCube detector. We present a complementary measurement using charged current muon neutrino events where the interaction vertex can be outside this volume. As a consequence of the large muon range the effective area is significantly larger but the field of view is restricted to the Northern Hemisphere. IceCube data from 2009 through 2015 have been analyzed using a likelihood approach based on the reconstructed muon energy and zenith angle. At the highest neutrino energies between 191 TeV and 8.3 PeV a significant astrophysical contribution is observed, excluding a purely atmospheric origin of these events at $5.6\,\sigma$ significance. The data are well described by an isotropic, unbroken power law flux with a normalization at 100 TeV neutrino energy of $\left(0.90^{+0.30}_{-0.27}\right)\times10^{-18}\,\mathrm{GeV^{-1}\,cm^{-2}\,s^{-1}\,sr^{-1}}$ and a hard spectral index of $\gamma=2.13\pm0.13$. The observed spectrum is harder in comparison to previous IceCube analyses with lower energy thresholds which may indicate a break in the astrophysical neutrino spectrum of unknown origin. The highest energy event observed has a reconstructed muon energy of $(4.5\pm1.2)\,\mathrm{PeV}$ which implies a probability of less than 0.005% for this event to be of atmospheric origin. Analyzing the arrival directions of all events with reconstructed muon energies above 200 TeV no correlation with known $\gamma$-ray sources was found. Using the high statistics of atmospheric neutrinos we report the currently best constraints on a prompt atmospheric muon neutrino flux originating from charmed meson decays which is below $1.06$ in units of the flux normalization of the model in Enberg et al. (2008)., Comment: 20 pages, 21 figures
Published: 2016

45. Constraints on axionlike particles with H.E.S.S. from the irregularity of the PKS 2155-304 energy spectrum

Author: Abramowski, A., Acero, F., Aharonian, F., Ait Benkhali, F., Akhperjanian, A.G., Angüner, E., Anton, G., Balenderan, S., Balzer, A., Barnacka, A., Becherini, Y., Becker Tjus, J., Bernlöhr, K., Birsin, E., Bissaldi, E., Biteau, J., Boisson, C., Bolmont, J., Bordas, P., Brucker, J., Brun, F., Brun, P., Bulik, T., Carrigan, S., Casanova, S., Cerruti, M., Chadwick, P.M., Chalme-Calvet, R., Chaves, R.C.G., Cheesebrough, A., Chrétien, M., Colafrancesco, S., Cologna, G., Conrad, J., Couturier, C., Dalton, M., Daniel, M.K., Davids, I.D., Degrange, B., Deil, C., deWilt, P., Dickinson, H.J., Djannati-Ataï, A., Domainko, W., Drury, L.O'C., Dubus, G., Dutson, K., Dyks, J., Dyrda, M., Edwards, T., Egberts, K., Eger, P., Espigat, P., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M.V., Fernandez, D., Fiasson, A., Fontaine, G., Förster, A., Fußling, M., Gajdus, M., Gallant, Y.A., Garrigoux, T., Gast, H., Giebels, B., Glicenstein, J.F., Göring, D., Grondin, M.-H., Grudzińska, M., Häffner, S., Hague, J.D., Hahn, J., Harris, J., Heinzelmann, G., Henri, G., Hermann, G., Hervet, O., Hillert, A., Hinton, J.A., Hofmann, W., Hofverberg, P., Holler, M., Horns, D., Jacholkowska, A., Jahn, C., Jamrozy, M., Janiak, M., Jankowsky, F., Jung, I., Kastendieck, M.A., Katarzyński, K., Katz, U., Kaufmann, S., Khélifi, B., Kieffer, M., Klepser, S., Klochkov, D., Kluźniak, W., Kneiske, T., Kolitzus, D., Komin, Nu., Kosack, K., Krakau, S., Krayzel, F., Krüger, P.P., Laffon, H., Lamanna, G., Lefaucheur, J., Lemoine-Goumard, M., Lenain, J.-P., Lennarz, D., Lohse, T., Lopatin, A., Lu, C.-C., Marandon, V., Marcowith, A., Marx, R., Maurin, G., Maxted, N., Mayer, M., McComb, T.J.L., Medina, M.C., Méhault, J., Menzler, U., Meyer, M., Moderski, R., Mohamed, M., Moulin, E., Murach, T., Naumann, C.L., de Naurois, M., Nedbal, D., Niemiec, J., Nolan, S.J., Oakes, L., Ohm, S., de Oña Wilhelmi, E., Opitz, B., Ostrowski, M., Oya, I., Panter, M., Parsons, R.D., Paz Arribas, M., Pekeur, N.W., Pelletier, G., Perez, J., Petrucci, P.-O., Peyaud, B., Pita, S., Poon, H., Pühlhofer, G., Punch, M., Quirrenbach, A., Raab, S., Raue, M., Reimer, A., Reimer, O., Renaud, M., de los Reyes, R., Rieger, F., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C.B., Sahakian, V., Sanchez, D.A., Santangelo, A., Schlickeiser, R., Schüssler, F., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Sol, H., Spengler, G., Spieß, F., Stawarz, L., Steenkamp, R., Stegmann, C., Stinzing, F., Stycz, K., Sushch, I., Szostek, A., Tavernet, J.-P., Terrier, R., Tluczykont, M., Trichard, C., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Viana, A., Vincent, P., Völk, H.J., Volpe, F., Vorster, M., Wagner, S.J., Wagner, P., Ward, M., Weidinger, M., Weitzel, Q., White, R., Wierzcholska, A., Willmann, P., Wörnlein, A., Wouters, D., Zacharias, M., Zajczyk, A., Zdziarski, A.A., Zech, A., Zechlin, H.-S., H.E.S.S. Collaboration, Laboratoire Univers et Particules de Montpellier (LUPM), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), HESS, A., Abramowski, F., Acero, F., Aharonian, F. A., Benkhali, A. G., Akhperjanian, E., Anguener, G., Anton, S., Balenderan, A., Balzer, A., Barnacka, Y., Becherini, J. B., Tju, K., Bernloehr, E., Birsin, Bissaldi, Elisabetta, J., Biteau, C., Boisson, J., Bolmont, P., Borda, J., Brucker, F., Brun, P., Brun, T., Bulik, S., Carrigan, S., Casanova, M., Cerruti, P. M., Chadwick, R., Chalme Calvet, R. C., G., A., Cheesebrough, M., Chretien, S., Colafrancesco, G., Cologna, J., Conrad, C., Couturier, M., Dalton, M. K., Daniel, I. D., David, B., Degrange, C., Deil, P., Dewilt, H. J., Dickinson, A., Djannati Atai, W., Domainko, L. O., '., G., Dubu, K., Dutson, J., Dyk, M., Dyrda, T., Edward, K., Egbert, P., Eger, P., Espigat, C., Farnier, S., Fegan, F., Feinstein, M. V., Fernande, D., Fernandez, A., Fiasson, G., Fontaine, A., Foerster, M., Fuessling, M., Gajdu, Y. A., Gallant, T., Garrigoux, H., Gast, B., Giebel, J. F., Glicenstein, D., Goering, M. . ., H., M., Grudzinska, S., Haeffner, J. D., Hague, J., Hahn, J., Harri, G., Heinzelmann, G., Henri, G., Hermann, O., Hervet, A., Hillert, J. A., Hinton, W., Hofmann, P., Hofverberg, M., Holler, D., Horn, A., Jacholkowska, C., Jahn, M., Jamrozy, M., Janiak, F., Jankowsky, I., Jung, M. A., Kastendieck, K., Katarzynski, U., Katz, S., Kaufmann, B., Khelifi, M., Kieffer, S., Klepser, D., Klochkov, W., Kluzniak, T., Kneiske, D., Kolitzu, N., Komin, K., Kosack, S., Krakau, F., Krayzel, P. P., Krueger, H., Laffon, G., Lamanna, J., Lefaucheur, M., Lemoine Goumard, J. . ., P., D., Lennarz, T., Lohse, A., Lopatin, C. . ., C., V., Marandon, A., Marcowith, R., Marx, G., Maurin, N., Maxted, M., Mayer, T. J., L., M. C., Medina, J., Mehault, U., Menzler, M., Meyer, R., Moderski, M., Mohamed, E., Moulin, T., Murach, C. L., Naumann, M. d., Nauroi, D., Nedbal, J., Niemiec, S. J., Nolan, L., Oake, S., Ohm, E. d., Ona, B., Opitz, M., Ostrowski, I., Oya, M., Panter, R. D., Parson, M. P., Arriba, N. W., Pekeur, G., Pelletier, J., Perez, P. . ., O., B., Peyaud, S., Pita, H., Poon, G., Puehlhofer, M., Punch, A., Quirrenbach, S., Raab, M., Raue, A., Reimer, O., Reimer, M., Renaud, R. d., Lo, F., Rieger, L., Rob, S., Rosier Lee, G., Rowell, B., Rudak, C. B., Rulten, V., Sahakian, D. A., Sanchez, A., Santangelo, R., Schlickeiser, F., Schuessler, A., Schulz, U., Schwanke, S., Schwarzburg, S., Schwemmer, H., Sol, G., Spengler, F., Spie, L., Stawarz, R., Steenkamp, C., Stegmann, F., Stinzing, K., Stycz, I., Sushch, A., Szostek, R., Terrier, M., Tluczykont, C., Trichard, K., Valeriu, C. v., Eldik, G., Vasileiadi, C., Venter, A., Viana, P., Vincent, H. J., Voelk, F., Volpe, M., Vorster, S. J., Wagner, P., Wagner, M., Ward, M., Weidinger, Q., Weitzel, R., White, A., Wierzcholska, P., Willmann, A., Woernlein, D., Wouter, M., Zacharia, A., Zajczyk, A. A., Zdziarski, A., Zech, H. . ., S., The H.E.S.S. Collaboration, Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO), and Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules)
Subjects: Electromagnetic field, Nuclear and High Energy Physics, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Photon, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Ciencias Físicas, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Física de Partículas y Campos, 01 natural sciences, 7. Clean energy, Standard Model, Physics::Geophysics, High Energy Physics - Experiment, purl.org/becyt/ford/1 [https], High Energy Physics - Experiment (hep-ex), 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], ddc:530, gamma-ray, 010303 astronomy & astrophysics, Boson, Physics, PKS 2155-304, High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Gamma rays, Gamma ray, Institut für Physik und Astronomie, purl.org/becyt/ford/1.3 [https], Axionlike particles, Pseudoscalar, Astrophysics - High Energy Astrophysical Phenomena, Gamma emission, CIENCIAS NATURALES Y EXACTAS, BL Lac object, H.E.S.S, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: Axionlike particles (ALPs) are hypothetical light (sub-eV) bosons predicted in some extensions of the Standard Model of particle physics. In astrophysical environments comprising high-energy gamma rays and turbulent magnetic fields, the existence of ALPs can modify the energy spectrum of the gamma rays for a sufficiently large coupling between ALPs and photons. This modification would take the form of an irregular behavior of the energy spectrum in a limited energy range. Data from the H.E.S.S. observations of the distant BL Lac object PKS 2155-304 (z = 0.116) are used to derive upper limits at the 95% C.L. on the strength of the ALP coupling to photons, $g_{\gamma a} < 2.1\times 10^{-11}$ GeV$^{-1}$ for an ALP mass between 15 neV and 60 neV. The results depend on assumptions on the magnetic field around the source, which are chosen conservatively. The derived constraints apply to both light pseudoscalar and scalar bosons that couple to the electromagnetic field., Comment: 13 pages, 7 figures, to appear in Phys.Rev.D
Published: 2013

46. Simulació d'una Lent de Laue per Radiació Gamma en el rang d'Energia d'1 MeV

Author: Perengüez Lopez, James, Universitat Politècnica de Catalunya. Departament d'Òptica i Optometria, Álvarez, José Manuel, and Isern Vilaboy, Jordi
Subjects: Astrofísica, Difracció electromagnètica, Enginyeria electrònica [Àrees temàtiques de la UPC], lente de laue, Mosaic Crystals, Òptica, Astrophysics, Laue lens, Gamma-ray, Física::Astronomia i astrofísica [Àrees temàtiques de la UPC], radiación gamma, Crystal Diraction, Nuclear Astrophysics, Instrumentació, Bragg Diraction, difracción
Abstract: The study of diffraction applied to Laue lenses is a very promising tool in the field of astrophysics of gamma radiation. In the present work we carried out a theoretical study and a computational simulation of a Laue lens that works in the energy range of 1 MeV. Treball final de màster oficial fet en col·laboració amb Universitat Autònoma de Barcelona (UAB), Universitat de Barcelona (UB) i Institut de ciències Fotòniques (ICFO) [ANGLÈS] The study of difraction applied to Laue lenses is a very promising tool in the field of astrophysics of gamma radiation. In the present work we carried out a theoretical study and a computational simulation of a Laue lens that works in the energy range of 1 MeV. First of all, we selected a geometry consisting of a concentric ring structure made of mosaic crystals; the materials used were germanium (Ge), copper (Cu) and silver (Ag). We considered two focal lengths of 10 m and 30 m. Some important parameters such as the arrangement of rings, the crystallographic planes of the crystals, the effective area of the lens and its point spread function, were obtained for these conditions. The results showed that the effective area increases when increases the focal distance, which represents a challenge in the design and construction of a Laue Lens. All calculations were developed using specialized software designed by a French research group, adapted and modified by the author to carry out this work. [CASTELLÀ] El estudio de la difracción aplicada a las lentes de Laue es una herramienta muy prometedora en el campo de la astrofísica de radiación gamma. En el presente trabajo llevamos a cabo un estudio teórico y una simulación computacional de una lente de Laue que trabaja en el rango de energía de 1 MeV. En primer lugar seleccionamos una geometría consistente de una estructura de anillos concéntricos hecha de cristales tipo mosaico, los materiales usados fueron germanio (Ge), cobre (Cu) y plata (Ag). Consideramos dos distancias focales de 10 m y 30 m. Algunos parámetros tales como el arreglo adecuado de los anillos, los planos cristalográficos de los cristales, el área efectiva y la PSF (point spread function), fueron obtenidos para estas condiciones. Los resultados mostraron que el área efectiva aumenta cuando aumenta la distancia focal lo cual representa un reto en el diseño y construcción de la lente. Todos los cálculos fueron desarrollados usando el software especializado diseñado por el grupo de investigación Francés, adaptado y modificado por el autor para llevar a cabo este trabajo. [CATALÀ] L'estudi de la difracció aplicada a les lents de Laue és una eina molt prometedora en el camp de l'astrofísica de radiació gamma. En el present treball duem a terme un estudi teòric i una simulació computacional d'una lent de Laue que treballa en el rang d'energia d'1 MeV. En primer lloc seleccionem una geometria consistent d'una estructura d'anells concèntrics feta de vidres tipus mosaic, els materials usats van ser germani (Ge), coure (Cu) i plata (Ag). Considerem dues distàncies focals de 10 mi 30 m. Alguns paràmetres com ara l'arranjament adequat dels anells, els plans cristal · logràfics dels vidres, l'àrea efectiva i la PSF (Point spread function), van ser obtinguts per aquestes condicions. Els resultats van mostrar que l'àrea efectiva augmenta quan augmenta la distància focal la qual cosa representa un repte en el disseny i construcció de la lent. Tots els càlculs van ser desenvolupats utilitzant el programari especialitzat dissenyat pel grup de recerca Francès, adaptat i modificat per l'autor per dur a terme aquest treball.
Published: 2013

47. Diffuse $\gamma$-ray emission from misaligned active galactic nuclei

Author: Marco Ajello, F. Calore, Luca Latronico, Fiorenza Donato, M. Di Mauro, and String Theory (ITFA, IoP, FNWI)
Subjects: Physics, education.field_of_study, Active galactic nucleus, Radio galaxy, Astrophysics::High Energy Astrophysical Phenomena, Population, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Galaxy, Luminosity, High Energy Physics - Phenomenology, Space and Planetary Science, Astrophysics::Solar and Stellar Astrophysics, gamma-ray, Blazar, education, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics::Galaxy Astrophysics, Luminosity function (astronomy), Fermi Gamma-ray Space Telescope, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: Active galactic nuclei (AGN) with jets seen at small viewing angles are the most luminous and abundant objects in the $\gamma$-ray sky. AGN with jets misaligned along the line-of-sight appear fainter in the sky, but are more numerous than the brighter blazars. We calculate the diffuse $\gamma$-ray emission due to the population of misaligned AGN (MAGN) unresolved by the Large Area Telescope (LAT) on the {\it Fermi} Gamma-ray Space Telescope ({\it Fermi}). A correlation between the $\gamma$-ray luminosity and the radio-core luminosity is established and demonstrated to be physical by statistical tests, as well as compatible with upper limits based on {\it Fermi}-LAT data for a large sample of radio-loud MAGN. We constrain the derived $\gamma$-ray luminosity function by means of the source count distribution of the radio galaxies (RGs) detected by the {\it Fermi}-LAT. We finally calculate the diffuse $\gamma$-ray flux due to the whole MAGN population. Our results demonstrate that the MAGN can contribute from 10% up to nearly the entire measured Isotropic Gamma-Ray Background (IGRB). We evaluate a theoretical uncertainty on the flux of almost an order of magnitude., Comment: Accepted for publication in ApJ
Published: 2013

48. Active Galactic Nuclei under the scrutiny of CTA

Author: H. Sol, A. Zech, C. Boisson, U. B. de, J. Biteau, J. . . L., B. Giebels, T. Hassan, Y. Inoue, K. Katarzynski, H. Krawczynski, N. Mirabal, J. Poutanen, F. Rieger, T. Totani, W. Benbow, M. Cerruti, M. Errando, L. Fallon, E. d. Gouveia, J. A. Hinton, S. Inoue, J. . . P., A. Neronov, K. Takahashi, H. Takami, R. White, CTA Consortium, Acharya B. S., Actis M., Aghajani T., BISSALDI, ELISABETTA, Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Institut de Física d'Altes Energies, Institut d'Estudis Espacials de Catalunya (IEEC-CSIC), NASA Goddard Space Flight Center (GSFC), Department of Mechanical System (Hiroshima University), Hiroshima University, INTEGRAL Science Data Center (ISDC), Geneva Observatory, Université de Genève = University of Geneva (UNIGE)-Université de Genève = University of Geneva (UNIGE), Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Max-Planck-Institut für Kernphysik (MPIK), Max-Planck-Gesellschaft, H., Sol, A., Zech, C., Boisson, U. B., De, J., Biteau, J. . ., L., B., Giebel, T., Hassan, Y., Inoue, K., Katarzynski, H., Krawczynski, N., Mirabal, J., Poutanen, F., Rieger, T., Totani, W., Benbow, M., Cerruti, M., Errando, L., Fallon, E. d., Gouveia, J. A., Hinton, S., Inoue, J. . ., P., A., Neronov, K., Takahashi, H., Takami, R., White, Cta, Consortium, Acharya, B. S., Actis, M., Aghajani, T., Bissaldi, Elisabetta, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and University of Geneva [Switzerland]-University of Geneva [Switzerland]
Subjects: Active galactic nucleus, High-energy astronomy, Astrophysics::High Energy Astrophysical Phenomena, Population, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 7. Clean energy, 01 natural sciences, High energy astrophysic, Cherenkov astronomy, High energy astrophysics, gamma-rays, Active Galactic Nuclei, Astrophysical jet, 0103 physical sciences, gamma-ray, Blazar, education, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, ComputingMilieux_MISCELLANEOUS, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, [PHYS]Physics [physics], Supermassive black hole, education.field_of_study, ta115, 010308 nuclear & particles physics, Astronomy, Astronomy and Astrophysics, GALÁXIAS, Cherenkov Telescope Array, 13. Climate action, Intergalactic travel, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Active Galactic Nuclei (hereafter AGN) produce powerful outflows which offer excellent conditions for efficient particle acceleration in internal and external shocks, turbulence, and magnetic reconnection events. The jets as well as particle accelerating regions close to the supermassive black holes (hereafter SMBH) at the intersection of plasma inflows and outflows, can produce readily detectable very high energy gamma-ray emission. As of now, more than 45 AGN including 41 blazars and 4 radiogalaxies have been detected by the present ground-based gamma-ray telescopes, which represents more than one third of the cosmic sources detected so far in the VHE gamma-ray regime. The future Cherenkov Telescope Array (CTA) should boost the sample of AGN detected in the VHE range by about one order of magnitude, shedding new light on AGN population studies, and AGN classification and unification schemes. CTA will be a unique tool to scrutinize the extreme high-energy tail of accelerated particles in SMBH environments, to revisit the central engines and their associated relativistic jets, and to study the particle acceleration and emission mechanisms, particularly exploring the missing link between accretion physics, SMBH magnetospheres and jet formation. Monitoring of distant AGN will be an extremely rewarding observing program which will inform us about the inner workings and evolution of AGN. Furthermore these AGN are bright beacons of gamma-rays which will allow us to constrain the extragalactic infrared and optical backgrounds as well as the intergalactic magnetic field, and will enable tests of quantum gravity and other "exotic" phenomena., 28 pages, 23 figures
Published: 2013

49. Search for Photon-Linelike Signatures from Dark Matter Annihilations with H.E.S.S

Author: S. Schwarzburg, J. Dyks, G. Heinzelmann, M. C. Medina, Y. A. Gallant, H.-S. Zechlin, Reinhard Schlickeiser, J.-P. Tavernet, Daniel Hampf, Michael Punch, Sabrina Casanova, Marek Jamrozy, Christo Venter, C. Jahn, Francois Brun, Gilles Henri, J. Becker Tjus, U. F. Katz, M. J. Vorster, Hugh Dickinson, C. L. Naumann, Helene Sol, R. D. Parsons, Matteo Cerruti, A. Zech, G. Cologna, C. van Eldik, Pascal Vincent, P.-O. Petrucci, F. Krayzel, F. Sheidaei, J. Harris, A. Marcowith, N. W. Pekeur, Anna Szostek, D. Göring, L. Fallon, S. Häffner, R. C. G. Chaves, Petter Hofverberg, M. V. Fernandes, Joachim Ripken, Werner Hofmann, Michał Ostrowski, A. Abramowski, D. Nekrassov, Dmitry Klochkov, Pierre Brun, Alicja Wierzcholska, S. Kaufmann, Daniel Sánchez, Thomas Lohse, Frank M. Rieger, L. O'c. Drury, Svenja Carrigan, Julien Lefaucheur, M. Renaud, P. Bordas, R. Steenkamp, S. Klepser, A. Barnacka, J. D. Hague, F. Stinzing, André Schulz, M. H. Grondin, P. M. Chadwick, M. Tluczykont, M. Paz Arribas, B. Giebels, J. Perez, F. Feinstein, E. Birsin, Dieter Horns, Julien Masbou, S. Heinz, Chia-Chun Lu, S. J. Fegan, A. Djannati-Ataï, Aion Viana, Ullrich Schwanke, J. Mehault, S. J. Nolan, G. Spengler, Henning Gast, P. Espigat, M. Dalton, Stefan Ohm, Joachim Hahn, S. Colafrancesco, Gavin Rowell, A. A. Zdziarski, Peter Eger, C. Stegmann, A. Lopatin, S. Pita, B. Opitz, A. G. Akhperjanian, M. Holler, Gilles Maurin, Nu. Komin, R. de los Reyes, A. Cheesebrough, I. Oya, Jacek Niemiec, Krzysztof Katarzynski, T. J. L. McComb, R. Moderski, Olaf Reimer, Jan Conrad, Catherine Boisson, Regis Terrier, Anna Zajczyk, D. Nedbal, C. Farnier, R. White, B. Peyaud, J.-P. Lenain, P. Dewilt, K. Stycz, J. Bolmont, W. Domainko, R. Kossakowski, A. Balzer, U. Menzler, B. Khélifi, J. F. Glicenstein, Iurii Sushch, M. Füßling, T. Garrigoux, Emmanuel Moulin, G. Hermann, E. de Oña Wilhelmi, G. Fontaine, I. Jung, B. Rudak, Kathrin Egberts, S. Rosier-Lees, B. Degrange, G. Lamanna, Tomasz Bulik, B. Glück, Andreas Hillert, A. Jacholkowska, M. Mohamed, M. Gajdus, V. Sahakian, I. D. Davids, Jim Hinton, Łukasz Stawarz, A. Fiasson, Heinrich J. Völk, A. Bochow, Stefan Wagner, Gisela Anton, M. Mayer, Yvonne Becherini, P.P. Krüger, K. Kosack, J. Brucker, Konrad Bernlöhr, Andreas Quirrenbach, Vincent Marandon, G. Pühlhofer, A. Reimer, M. Naumann-Godo, Fabio Acero, Michal Dyrda, Michael Zacharias, M. de Naurois, M. Panter, Martin Ward, Cameron B Rulten, S. Balenderan, Dirk Lennarz, Serguei Vorobiov, M. K. Daniel, G. Pelletier, C. Trichard, Felix Aharonian, H. Laffon, J. L. Skilton, Jonathan Biteau, K. Valerius, S. Schwemmer, Andrea Santangelo, Guillaume Dubus, A. Förster, Martin Raue, L. Rob, D. Fernandez, N. Nguyen, M. A. Kastendieck, N. Maxted, G. Vasileiadis, K. Dutson, Christoph Deil, T. Kneiske, M. Lemoine-Goumard, Francesca Volpe, Denis Wouters, W. Kluźniak, C. Couturier, Institut für Experimentalphysik [Hamburg], Universität Hamburg (UHH), Laboratoire Univers et Particules de Montpellier (LUPM), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Kernphysik (MPIK), Max-Planck-Gesellschaft, Dublin Institute for Advanced Studies (DIAS), National Academy of Sciences of the Republic of Armenia [Yerevan] (NAS RA), Yerevan Physics Institute, Yerevan State University, Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Department of Physics [Durham University], Durham University, Deutsches Elektronen-Synchrotron [Zeuthen] (DESY), Helmholtz-Gemeinschaft = Helmholtz Association, University of Potsdam = Universität Potsdam, Nicolaus Copernicus University [Toruń], Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Astronomisches Institut der Ruhr-Universität Bochum, Ruhr-Universität Bochum [Bochum], Humboldt University Of Berlin, Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut für Astronomie und Astrophysik [Tübingen] (IAAT), Eberhard Karls Universität Tübingen = Eberhard Karls University of Tuebingen, CEA- Saclay (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Astronomical Observatory [Warsaw], Faculty of Physics [Warsaw] (FUW), University of Warsaw (UW)-University of Warsaw (UW), North-West University [Potchefstroom] (NWU), University of the Witwatersrand [Johannesburg] (WITS), Zentrum für Astronomie der Universität Heidelberg (ZAH), Universität Heidelberg [Heidelberg] = Heidelberg University, Oskar Klein Centre [Stockholm], Stockholm University, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Namibia University of Science and Technology (NUST), University of South Australia [Adelaide], APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Department of Physics and Astronomy [Leicester], University of Leicester, Instytut Fizyki Jądrowej PAN (IFJ), Polskiej Akademii Nauk, Leopold Franzens Universität Innsbruck - University of Innsbruck, Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Max Planck Institute for Astronomy (MPIA), Uniwersytet Jagielloński w Krakowie = Jagiellonian University (UJ), Torun Centre for Astronomy (TCfA), Physikalisches Institut [Erlangen], Institut für Theoretische Physik IV [Bochum] (ITP4), Space Research Centre [Torun], Polska Akademia Nauk = Polish Academy of Sciences (PAN), Astronomical Institute of Charles University, Charles University [Prague] (CU), Space Research Centre [Leicester], HESS, Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), GLAST, Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Universität Potsdam, Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Humboldt-Universität zu Berlin, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Unit for Space Physics, North-West University, South-Africa, Unit for Space Physics, North-West University, APC - Cosmologie, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Universität Heidelberg [Heidelberg], Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), 11749903 - Krüger, Petrus Paulus, 22050574 - Pekeur, Nicolette Whilna, 12006653 - Venter, Christo, 22164405 - Sheidaei, Farzaneh, 12792322 - Vorster, Michael Johannes, and 23909196 - Casanova, Sabrina
Subjects: [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], 95.85.Pw, Ciencias Físicas, Milky Way, Astrophysics::High Energy Astrophysical Phenomena, Dark matter, General Physics and Astronomy, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 7. Clean energy, 01 natural sciences, Gamma-ray, purl.org/becyt/ford/1 [https], 0103 physical sciences, ddc:550, 010306 general physics, Astrophysics::Galaxy Astrophysics, Line (formation), Astroparticle physics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Annihilation, 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Gamma ray, Institut für Physik und Astronomie, purl.org/becyt/ford/1.3 [https], Gamma-Rays, Astronomía, Dark Matter Annihilations, Dark matter halo, 95.35.+d, Halo, Astrophysics - High Energy Astrophysical Phenomena, CIENCIAS NATURALES Y EXACTAS
Abstract: Gamma-ray line signatures can be expected in the very-high-energy (VHE; E_\gamma > 100 GeV) domain due to self-annihilation or decay of dark matter (DM) particles in space. Such a signal would be readily distinguishable from astrophysical \gamma-ray sources that in most cases produce continuous spectra which span over several orders of magnitude in energy. Using data collected with the H.E.S.S. \gamma-ray instrument, upper limits on line-like emission are obtained in the energy range between ~500 GeV and ~25 TeV for the central part of the Milky Way halo and for extragalactic observations, complementing recent limits obtained with the Fermi-LAT instrument at lower energies. No statistically significant signal could be found. For monochromatic \gamma-ray line emission, flux limits of (2x10^-7 - 2x10^-5) m^-2 s^-1 sr^-1 and (1x10^-8 - 2x10^-6) m^-2 s^-1 sr^-1 are obtained for the central part of the Milky Way halo and extragalactic observations, respectively. For a DM particle mass of 1 TeV, limits on the velocity-averaged DM annihilation cross section < \sigma v >(\chi\chi -> \gamma\gamma) reach ~10^-27 cm^3 s^-1, based on the Einasto parametrization of the Galactic DM halo density profile., Comment: 6 pages, 4 figures, accepted for publication in Phys. Rev. Lett
Published: 2013

50. Origin of TeV Galactic cosmic rays

Author: A. Neronov, D.V. Semikoz, INTEGRAL Science Data Center (ISDC), Geneva Observatory, Université de Genève = University of Geneva (UNIGE)-Université de Genève = University of Geneva (UNIGE), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), University of Geneva [Switzerland]-University of Geneva [Switzerland], APC - THEORIE, Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut für theoretische Physik, Universität Hamburg (UHH)-Universität Hamburg (UHH), Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)
Subjects: Nuclear and High Energy Physics, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Cosmic ray, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, 7. Clean energy, High Energy Physics - Phenomenology (hep-ph), Pulsar, 0103 physical sciences, gamma-ray, 010306 general physics, 010303 astronomy & astrophysics, Cosmic rays, Astrophysics::Galaxy Astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, [PHYS]Physics [physics], [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Gamma ray, Astronomy, Galaxy, Interstellar medium, High Energy Physics - Phenomenology, Supernova, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Energy (signal processing), Fermi Gamma-ray Space Telescope
Abstract: We consider a possibility of identification of sources of cosmic rays (CR) of the energy above 1 TeV via observation of degree-scale extended gamma-ray emission which traces the locations of recent sources in the Galaxy. Such emission in the energy band above 100 GeV is produced by CR nuclei and electrons released by the sources and spreading into the interstellar medium. We use the data from the Fermi gamma-ray telescope to locate the degree-scale 100 GeV gamma-ray sources. We find that the number of such sources and their overall power match to those expected when CRs injection events happen every ~100 yr in portions of ~1e50 erg. We find that most of the sources are associated to pulsars with spin down age less than ~30 kyr and hence to the recent supernova explosions. This supports the hypothesis of supernova origin of Galactic CRs. We notice that the degree-scale extended emission does not surround shell-like supernova remnants without pulsars. Based on this observation, we argue that the presence of the pulsar is essential for the CR acceleration process. We expect that a significant fraction of the degree-scale sources should be detectable as extended sources with km3-scale neutrino detectors., Comment: 14 pages, 14 figures, accepted for publication in Phys.Rev.D
Published: 2012

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