Author: "Kent, S." / Topic: physics - Searchworks@Jio Institute Digital Library Search Results

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138 results on '"Kent, S."'

1. No evidence for orbital clustering in the extreme trans-Neptunian objects

Author: Napier, K. J., Gerdes, D. W., Lin, Hsing Wen, Hamilton, S. J., Bernstein, G. M., Bernardinelli, P. H., Abbott, T. M. C., Aguena, M., Annis, J., Avila, S., Bacon, D., Bertin, E., Brooks, D., Burke, D. L., Carnero Rosell, A., Carrasco Kind, M., Carretero, J., Costanzi, M., da Costa, L. N., De Vicente, J., Diehl, H. T., Doel, P., Everett, S., Ferrero, I., Fosalba, P., García-Bellido, J., Gruen, D., Gruendl, R. A., Gutierrez, G., Hollowood, D. L., Honscheid, K., Hoyle, B., James, D. J., Kent, S., Kuehn, K., Kuropatkin, N., Maia, M. A. G., Menanteau, F., Miquel, R., Morgan, R., Palmese, A., Paz-Chinchón, F., Plazas, A. A., Sanchez, E., Scarpine, V., Serrano, S., Sevilla-Noarbe, I., Smith, M., Suchyta, E., Swanson, M. E. C., To, C., Walker, A. R., Wilkinson, R. D., DES Collaboration, Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Generalitat de Catalunya, Instituto Nacional de Ciência e Tecnologia (Brasil), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), DES, Napier, K. J., Gerdes, D. W., Lin, Hsing Wen, Hamilton, S. J., Bernstein, G. M., Bernardinelli, P. H., Abbott, T. M. C., Aguena, M., Annis, J., Avila, S., Bacon, D., Bertin, E., Brooks, D., Burke, D. L., Carnero Rosell, A., Carrasco Kind, M., Carretero, J., Costanzi, M., da Costa, L. N., De Vicente, J., Diehl, H. T., Doel, P., Everett, S., Ferrero, I., Fosalba, P., García-Bellido, J., Gruen, D., Gruendl, R. A., Gutierrez, G., Hollowood, D. L., Honscheid, K., Hoyle, B., James, D. J., Kent, S., Kuehn, K., Kuropatkin, N., Maia, M. A. G., Menanteau, F., Miquel, R., Morgan, R., Palmese, A., Paz-Chinchón, F., Plazas, A. A., Sanchez, E., Scarpine, V., Serrano, S., Sevilla-Noarbe, I., Smith, M., Suchyta, E., Swanson, M. E. C., To, C., Walker, A. R., Wilkinson, R. D., Des, Collaboration, Napier, K. J. [0000-0003-4827-5049], Gerdes, D. W. [0000-0001-6942-2736], Lin, Hsing Wen [0000-0001-7737-6784], Hamilton, S. J. [0000-0002-6126-8487], Bernstein, G. M. [0000-0002-8613-8259], Bernardinelli, P. H. [0000-0003-0743-9422], Annis, J. [0000-0002-0609-3987], Bertin, E. [0000-0002-3602-3664], Brooks, D. [0000-0002-8458-5047], Burke, D. L. [0000-0003-1866-1950], Carnero Rosell, A. [0000-0003-3044-5150], Carrasco Kind, M. [0000-0002-4802-3194], Carretero, J. [0000-0002-3130-0204], da Costa, L. N. [0000-0002-7731-277X], De Vicente, J. [0000-0001-8318-6813], Diehl, H. T. [0000-0002-8357-7467], Fosalba, P. [0000-0002-1510-5214], García-Bellido, J. [0000-0002-9370-8360], Gruen, D. [0000-0003-3270-7644], Gruendl, R. A. [0000-0002-4588-6517], Hollowood, D. L. [0000-0002-9369-4157], James, D. J. [0000-0001-5160-4486], Kent, S. [0000-0003-4207-7420], Kuropatkin, N. [0000-0003-2511-0946], Menanteau, F. [0000-0002-1372-2534], Miquel, R. [0000-0002-6610-4836], Morgan, R. [0000-0002-7016-5471], Palmese, A. [0000-0002-6011-0530], Plazas, A. A. [0000-0002-2598-0514], Sanchez, E. [0000-0002-9646-8198], Smith, M. [0000-0002-3321-1432], Swanson, M. E. C. [0000-0002-1488-8552], Walker, A. R. [0000-0002-7123-8943], Apollo - University of Cambridge Repository, Napier, KJ [0000-0003-4827-5049], Gerdes, DW [0000-0001-6942-2736], Lin, HW [0000-0001-7737-6784], Hamilton, SJ [0000-0002-6126-8487], Bernstein, GM [0000-0002-8613-8259], Bernardinelli, PH [0000-0003-0743-9422], Annis, J [0000-0002-0609-3987], Bertin, E [0000-0002-3602-3664], Brooks, D [0000-0002-8458-5047], Burke, DL [0000-0003-1866-1950], Rosell, AC [0000-0003-3044-5150], Kind, MC [0000-0002-4802-3194], Carretero, J [0000-0002-3130-0204], Da Costa, LN [0000-0002-7731-277X], De Vicente, J [0000-0001-8318-6813], Diehl, HT [0000-0002-8357-7467], Fosalba, P [0000-0002-1510-5214], García-Bellido, J [0000-0002-9370-8360], Gruen, D [0000-0003-3270-7644], Gruendl, RA [0000-0002-4588-6517], Hollowood, DL [0000-0002-9369-4157], James, DJ [0000-0001-5160-4486], Kent, S [0000-0003-4207-7420], Kuropatkin, N [0000-0003-2511-0946], Menanteau, F [0000-0002-1372-2534], Miquel, R [0000-0002-6610-4836], Morgan, R [0000-0002-7016-5471], Palmese, A [0000-0002-6011-0530], Plazas, AA [0000-0002-2598-0514], Sanchez, E [0000-0002-9646-8198], Smith, M [0000-0002-3321-1432], Swanson, MEC [0000-0002-1488-8552], and Walker, AR [0000-0002-7123-8943]
Subjects: Solar System, Trans-Neptunian objects, Detached object, FOS: Physical sciences, 0603 philosophy, ethics and religion, 01 natural sciences, Kuiper belt, 0103 physical sciences, Earth and Planetary Sciences (miscellaneous), Planetary science, Kuiper Belt, Trans-Neptunian object, Detached objects, 10. No inequality, Cluster analysis, 010303 astronomy & astrophysics, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Solar system, 1528, 1255, 1705, 893, 376, Astrophysics - Earth and Planetary Astrophysics, Astronomy, Astronomy and Astrophysics, 06 humanities and the arts, Trans-neptunian objects, Geophysics, Space and Planetary Science, astro-ph.EP, Physics::Space Physics, 060302 philosophy, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Planetary Science
Abstract: Napier, K. J., et al. (DES Collaboration), The apparent clustering in longitude of perihelion ϖ and ascending node Ω of extreme trans-Neptunian objects (ETNOs) has been attributed to the gravitational effects of an unseen 5–10 Earth-mass planet in the outer solar system. To investigate how selection bias may contribute to this clustering, we consider 14 ETNOs discovered by the Dark Energy Survey, the Outer Solar System Origins Survey, and the survey of Sheppard and Trujillo. Using each survey's published pointing history, depth, and TNO tracking selections, we calculate the joint probability that these objects are consistent with an underlying parent population with uniform distributions in ϖ and Ω. We find that the mean scaled longitude of perihelion and orbital poles of the detected ETNOs are consistent with a uniform population at a level between 17% and 94% and thus conclude that this sample provides no evidence for angular clustering., The DES participants from Spanish institutions are partially supported by MICINN under grants ESP2017-89838, PGC2018-094773, PGC2018-102021, SEV2016-0588, SEV-2016-0597, and MDM-2015-0509, some of which include ERDF funds from the European Union. The IFAE is partially funded by the CERCA program of the Generalitat de Catalunya. Research leading to these results has received funding from the European Research Council under the European Unionʼs Seventh Framework Program (FP7/ 2007-2013), including ERC grant agreements 240672, 291329, and 306478. We acknowledge support from the Brazilian Instituto Nacional de Ciência e Tecnologia (INCT) do e-Universo (CNPq grant 465376/2014-2).
Published: 2021

2. NICER Detection of Thermal X-Ray Pulsations from the Massive Millisecond Pulsars PSR J0740+6620 and PSR J1614–2230

Author: Alexander J. Dittmann, M. Coleman Miller, Michael T. Wolff, Gilles Theureau, Keith C. Gendreau, Lucas Guillemot, Wynn C. G. Ho, Ismaël Cognard, Zaven Arzoumanian, Sebastien Guillot, Slavko Bogdanov, Kent S. Wood, Matthew Kerr, Paul S. Ray, 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), Centre National d'Études Spatiales [Toulouse] (CNES), 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), Laboratoire Univers et Théories (LUTH (UMR_8102)), 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), 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 Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
Subjects: [PHYS]Physics [physics], High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Neutron Star Interior Composition Explorer, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, X-ray binary, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, 16. Peace & justice, 01 natural sciences, Spectral line, Neutron star, Pulsar, Space and Planetary Science, Millisecond pulsar, Thermal radiation, [SDU]Sciences of the Universe [physics], 0103 physical sciences, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Data reduction
Abstract: We report the detection of X-ray pulsations from the rotation-powered millisecond-period pulsars PSR J0740+6620 and PSR J1614-2230, two of the most massive neutron stars known, using observations with the Neutron Star Interior Composition Explorer (NICER). We also analyze X-ray Multi-Mirror Mission (XMM-Newton) data for both pulsars to obtain their time-averaged fluxes and study their respective X-ray fields. PSR J0740+6620 exhibits a broad double-peaked profile with a separation of ~0.4 in phase. PSR J1614-2230, on the other hand, has a broad single-peak profile. The broad modulations with soft X-ray spectra of both pulsars are indicative of thermal radiation from one or more small regions of the stellar surface. We show the NICER detections of X-ray pulsations for both pulsars and also discuss the phase relationship to their radio pulsations. In the case of PSR J0740+6620, this paper documents the data reduction performed to obtain the pulsation detection and prepare for pulse profile modeling analysis., Submitted to The Astrophysical Journal Letters
Published: 2021
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3. A NICER View of Spectral and Profile Evolution for Three X-ray Emitting Millisecond Pulsars

Author: Zaven Arzoumanian, Lauren Lugo, Paul S. Ray, Slavko Bogdanov, Julia Deneva, Scott M. Ransom, Matthew Kerr, Elizabeth Spano, Keith C. Gendreau, Christo Venter, Andrea N. Lommen, Sebastien Guillot, Kent S. Wood, Natalia Lewandowska, D. M. Rowan, Craig B. Markwardt, Alice K. Harding, Renee M. Ludlam, Zaynab Ghazi, Teruaki Enoto, 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), Centre National d'Études Spatiales [Toulouse] (CNES), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), and 12006653 - Venter, Christo
Subjects: 010504 meteorology & atmospheric sciences, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Context (language use), Astrophysics, 7. Clean energy, 01 natural sciences, Neutron stars, X-ray astronomy, Pulsar, Millisecond pulsar, 0103 physical sciences, Emission spectrum, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Millisecond pulsars, Neutron Star Interior Composition Explorer, Astronomy and Astrophysics, Pulse (physics), Neutron star, 13. Climate action, Space and Planetary Science, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: We present two years of Neutron star Interior Composition Explorer (NICER) X-ray observations of three energetic rotation-powered millisecond pulsars (MSPs): PSRs B1937+21, B1821-24, and J0218+4232. We fit Gaussians and Lorentzians to the pulse profiles for different energy sub-bands of the soft X-ray regime to measure the energy dependence of pulse separation and width. We find that the separation between pulse components of PSR J0218+4232 decreases with increasing energy at $\gt 3\sigma$ confidence. The 95% upper limit on pulse separation evolution for PSRs B1937+21 and B1821-24 is less than 2 milliperiods per keV. Our phase-resolved spectral results provide updated constraints on the non-thermal X-ray emission of these three pulsars. The photon indices of the modeled X-ray emission spectra for each pulse component of PSR B1937+21 are inconsistent with each other at the 90% confidence level, suggesting different emission origins for each pulse. We find that the PSR B1821-24 and PSR J0218+4232 emission spectra are invariant with phase at the 90% confidence level. We describe the implications of our profile and spectral results in the context of equatorial current sheet emission models for these three MSPs with non-thermal, magnetospheric X-ray emission., Comment: 16 pages, 13 figures, accepted for publication in ApJ
Published: 2020
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4. Constraining the Neutron Star Mass–Radius Relation and Dense Matter Equation of State with $NICER$. I. The Millisecond Pulsar X-Ray Data Set

Author: Reilly Milburn, Frederick K. Lamb, James W. Kellogg, James F. Steiner, Paul S. Ray, Anna L. Watts, Andrea N. Lommen, Kent S. Wood, M. Coleman Miller, Slavko Bogdanov, Michael T. Wolff, Feryal Özel, Charles Baker, Jesse Zeldes, Matthew Kerr, Michi Baubock, Deepto Chakrabarty, Dimitrios Psaltis, Zaven Arzoumanian, Ronald A. Remillard, Sergio Montano, Renee M. Ludlam, Teruaki Enoto, Tod E. Strohmayer, Keith C. Gendreau, Sebastien Guillot, Thomas E. Riley, Craig B. Markwardt, Takashi Okajima, Wynn C. G. Ho, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), 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), Centre National d'Études Spatiales [Toulouse] (CNES), 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), High Energy Astrophys. & Astropart. Phys (API, FNWI), and Gravitation and Astroparticle Physics Amsterdam
Subjects: Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Equation of state, Neutron Star Interior Composition Explorer, 010504 meteorology & atmospheric sciences, Astrophysics::High Energy Astrophysical Phenomena, Flux, FOS: Physical sciences, Astronomy and Astrophysics, Radius, Astrophysics, 01 natural sciences, 7. Clean energy, Neutron star, 13. Climate action, Space and Planetary Science, Millisecond pulsar, 0103 physical sciences, Thermal, Spectroscopy, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, 0105 earth and related environmental sciences
Abstract: We present the set of deep Neutron Star Interior Composition Explorer (NICER) X-ray timing observations of the nearby rotation-powered millisecond pulsars PSRs J0437-4715, J0030+0451, J1231-1411, and J2124-3358, selected as targets for constraining the mass-radius relation of neutron stars and the dense matter equation of state via modeling of their pulsed thermal X-ray emission. We describe the instrument, observations, and data processing/reduction procedures, as well as the series of investigations conducted to ensure that the properties of the data sets are suitable for parameter estimation analyses to produce reliable constraints on the neutron star mass-radius relation and the dense matter equation of state. We find that the long-term timing and flux behavior and the Fourier-domain properties of the event data do not exhibit any anomalies that could adversely affect the intended measurements. From phase-selected spectroscopy, we find that emission from the individual pulse peaks is well described by a single-temperature hydrogen atmosphere spectrum, with the exception of PSR J0437-4715, for which multiple temperatures are required., 28 pages, 9 figures; accepted for publication in the Astrophysical Journal Letters
Published: 2019
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5. Dark Energy Survey year 1 results: Joint analysis of galaxy clustering, galaxy lensing, and CMB lensing two-point functions

Author: Abbott, T. M. C., Abdalla, F. B., Alarcon, A., Allam, S., Annis, J., Avila, S., Aylor, K., Banerji, M., Banik, N., Baxter, E. J., Bechtol, K., Becker, M. R., Benson, B. A., Bernstein, G. M., Bertin, E., Bianchini, F., Blazek, J., Bleem, L., Bleem, L. E., Bridle, S. L., Brooks, D., Buckley-Geer, E., Burke, D. L., Carlstrom, J. E., Rosell, A. Carnero, Kind, M. Carrasco, Carretero, J., Castander, F. J., Cawthon, R., Chang, C., Chang, C. L., Cho, H-M., Choi, A., Chown, R., Crawford, T. M., Crites, A. T., Crocce, M., Cunha, C. E., D'Andrea, C. B., da Costa, L. N., Davis, C., de Haan, T., DeRose, J., Desai, S., De Vicente, J., Diehl, H. T., Dietrich, J. P., Dobbs, M. A., Dodelson, S., Doel, P., Drlica-Wagner, A., Eifler, T. F., Elvin-Poole, J., Everett, W. B., Flaugher, B., Fosalba, P., Friedrich, O., Frieman, J., Garc��a-Bellido, J., Gatti, M., Gaztanaga, E., George, E. M., Gerdes, D. W., Giannantonio, T., Gruen, D., Gruendl, R. A., Gschwend, J., Gutierrez, G., Halverson, N. W., Harrington, N. L., Hartley, W. G., Holder, G. P., Hollowood, D. L., Holzapfel, W. L., Honscheid, K., Hou, Z., Hoyle, B., Hrubes, J. D., Huterer, D., Jain, B., James, D. J., Jarvis, M., Jeltema, T., Johnson, M. W. G., Johnson, M. D., Kent, S., Kirk, D., Knox, L., Kokron, N., Krause, E., Kuehn, K., Lahav, O., Lee, A. T., Leitch, E. M., Li, T. S., Lima, M., Lin, H., Luong-Van, D., MacCrann, N., Maia, M. A. G., Manzotti, A., Marrone, D. P., Marshall, J. L., Martini, P., McMahon, J. J., Menanteau, F., Meyer, S. S., Miquel, R., Mocanu, L. M., Mohr, J. J., Muir, J., Natoli, T., Nicola, A., Nord, B., Omori, Y., Padin, S., Pandey, S., Plazas, A. A., Porredon, A., Prat, J., Pryke, C., Rau, M. M., Reichardt, C. L., Rollins, R. P., Romer, A. K., Roodman, A., Ross, A. J., Rozo, E., Ruhl, J. E., Rykoff, E. S., Samuroff, S., S��nchez, C., Sanchez, E., Sayre, J. T., Scarpine, V., Schaffer, K. K., Secco, L. F., Serrano, S., Sevilla-Noarbe, I., Sheldon, E., Shirokoff, E., Simard, G., Smith, M., Soares-Santos, M., Sobreira, F., Staniszewski, Z., Stark, A. A., Story, K. T., Suchyta, E., Swanson, M. E. C., Tarle, G., Thomas, D., Troxel, M. A., Tucker, D. L., Vanderlinde, K., Vieira, J. D., Vielzeuf, P., Vikram, V., Walker, A. R., Wechsler, R. H., Weller, J., Williamson, R., Wu, W. L. K., Yanny, B., Zahn, O., Zhang, Y., Zuntz, J., Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), DES, and SPT
Subjects: Physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), 010308 nuclear & particles physics, Cosmic microwave background, FOS: Physical sciences, Context (language use), Field (mathematics), Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Omega, Galaxy, Cosmology, South Pole Telescope, 0103 physical sciences, Dark energy, astro-ph.CO, LENTES GRAVITACIONAIS, 010306 general physics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Weak gravitational lensing, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We perform a joint analysis of the auto and cross-correlations between three cosmic fields: the galaxy density field, the galaxy weak lensing shear field, and the cosmic microwave background (CMB) weak lensing convergence field. These three fields are measured using roughly 1300 sq. deg. of overlapping optical imaging data from first year observations of the Dark Energy Survey and millimeter-wave observations of the CMB from both the South Pole Telescope Sunyaev-Zel'dovich survey and Planck. We present cosmological constraints from the joint analysis of the two-point correlation functions between galaxy density and galaxy shear with CMB lensing. We test for consistency between these measurements and the DES-only two-point function measurements, finding no evidence for inconsistency in the context of flat $\Lambda$CDM cosmological models. Performing a joint analysis of five of the possible correlation functions between these fields (excluding only the CMB lensing autospectrum) yields $S_{8}\equiv \sigma_8\sqrt{\Omega_{\rm m}/0.3} = 0.782^{+0.019}_{-0.025}$ and $\Omega_{\rm m}=0.260^{+0.029}_{-0.019}$. We test for consistency between these five correlation function measurements and the Planck-only measurement of the CMB lensing autospectrum, again finding no evidence for inconsistency in the context of flat $\Lambda$CDM models. Combining constraints from all six two-point functions yields $S_{8}=0.776^{+0.014}_{-0.021}$ and $\Omega_{\rm m}= 0.271^{+0.022}_{-0.016}$. These results provide a powerful test and confirmation of the results from the first year DES joint-probes analysis., Comment: 20 pages, 7 figures
Published: 2019
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6. NICER and Fermi GBM Observations of the First Galactic Ultraluminous X-ray Pulsar Swift J0243.6+6124

Author: Kent S. Wood, Wynn C. G. Ho, Keith C. Gendreau, Craig B. Markwardt, Deepto Chakrabarty, Gaurava K. Jaisawal, Christian Malacaria, Beverly LaMarr, Sebastien Guillot, Mercedes Ramos-Lerate, John P. Doty, Matthew Kerr, Michael Vezie, Peter Jenke, Tod E. Strohmayer, Gregory Y. Prigozhin, Michael T. Wolff, Colleen A. Wilson-Hodge, Feryal Özel, Zaven Arzoumanian, Ronald A. Remillard, Paul S. Ray, 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), Centre National d'Études Spatiales [Toulouse] (CNES), NICER, Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)
Subjects: Accretion, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Spectral line, Article, Luminosity, X-rays: binaries, Pulsar, accretion, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, individual (SWIFT J0243.6+6124) [Pulsars], Astrophysics::Galaxy Astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Neutron Star Interior Composition Explorer, Accretion (meteorology), 010308 nuclear & particles physics, accretion disks, Astronomy and Astrophysics, Neutron star, pulsars: individual, 13. Climate action, Space and Planetary Science, Accretion disks, binaries [X-rays], Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Fermi Gamma-ray Space Telescope, X-ray pulsar
Abstract: Swift J0243.6+6124 is a newly discovered Galactic Be/X-ray binary, revealed in late September 2017 in a giant outburst with a peak luminosity of 2E+39 (d/7 kpc)^2 erg/s (0.1-10 keV), with no formerly reported activity. At this luminosity, Swift J0243.6+6124 is the first known galactic ultraluminous X-ray pulsar. We describe Neutron star Interior Composition Explorer (NICER)} and Fermi Gamma-ray Burst Monitor (GBM) timing and spectral analyses for this source. A new orbital ephemeris is obtained for the binary system using spin-frequencies measured with GBM and 15-50 keV fluxes measured with the Neil Gehrels Swift Observatory Burst Alert Telescope to model the system's intrinsic spin-up. Power spectra measured with NICER show considerable evolution with luminosity, including a quasi-periodic oscillation (QPO) near 50 mHz that is omnipresent at low luminosity and has an evolving central frequency. Pulse profiles measured over the combined 0.2-100 keV range show complex evolution that is both luminosity and energy dependent. Near the critical luminosity of L~1E+38 erg/s, the pulse profiles transition from single-peaked to double peaked, the pulsed fraction reaches a minimum in all energy bands, and the hardness ratios in both NICER and GBM show a turn-over to softening as the intensity increases. This behavior repeats as the outburst rises and fades, indicating two distinct accretion regimes. These two regimes are suggestive of the accretion structure on the neutron star surface transitioning from a Coulomb collisional stopping mechanism at lower luminosities to a radiation-dominated stopping mechanism at higher luminosities. This is the highest observed (to date) value of the critical luminosity, suggesting a magnetic field of B ~1E+13 G., 35 pages, 7 figures (main text), 5 figures (appendix); Accepted for publication in ApJ on June 19, 2018
Published: 2018
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7. A Luminous and Highly-variable Gamma-ray Flare Following the 2017 Periastron of PSR B1259-63/LS 2883

Author: Matthew Kerr, Robin H. D. Corbet, Tyrel J. Johnson, Kent S. Wood, C. C. Cheung, Paul S. Ray, and Nicola Omodei
Subjects: 010504 meteorology & atmospheric sciences, Be star, Astrophysics::High Energy Astrophysical Phenomena, Flux, FOS: Physical sciences, Astrophysics, 01 natural sciences, law.invention, Spitzer Space Telescope, Pulsar, law, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Gamma ray, Astronomy and Astrophysics, Neutron star, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Flare, Fermi Gamma-ray Space Telescope
Abstract: Three periastron passages of the PSR B1259$-$63/LS 2883 binary system, consisting of a 48 ms rotation-powered pulsar and a $\sim30$ M$_{\odot}$ Be star, have been observed by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope, in 2010, 2014, and 2017. During the most-recent periastron passage, sustained low-level gamma-ray emission was observed over a $\sim3$-week long interval immediately after periastron, which was followed by an interval of no emission. Sporadic flares were detected starting 40 days post-periastron and lasted approximately 50 days, during which the emission displayed significant spectral curvature, variability on timescales as short as 1.5 minutes, and peak flux levels well in excess of the pulsar spin-down power. By contrast, during the 2010 and 2014 periastron passages, significant gamma-ray emission was not observed with the LAT until 30 and 32 days post-periastron, respectively. The previous flares did not exhibit spectral curvature, showed no short term variability, and did not exceed the pulsar spin-down power. The high flux and short timescales observed in 2017 suggest significant beaming of the emission is required and constrain the size of the emission region. The flares occur long enough after periastron that the neutron star should already have passed through the extended disk-like outflow, thus constraining options for target material and seed photon sources for inverse Compton models., Comment: Accepted for publication in the Astrophysical Journal (2 July 2018), v2 matches accepted version
Published: 2018
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8. A Search for Optical Emission from Binary-Black-Hole Merger GW170814 with the Dark Energy Camera

Author: Doctor, Z., Kessler, R., Herner, K., Palmese, A., Soares-Santos, M., Annis, J., Brout, D., Holz, D. E., Sako, M., Rest, A., Cowperthwaite, P., Berger, E., Foley, R. J., Conselice, C. J., Gill, M. S. S., Allam, S., Balbinot, E., Butler, R. E., Chen, H. -Y., Chornock, R., Cook, E., Diehl, H. T., Farr, B., Fong, W., Frieman, J., Fryer, C., García-Bellido, J., Margutti, R., Marshall, J. L., Matheson, T., Metzger, B. D., Nicholl, M., Paz-Chinchón, F., Salim, S., Sauseda, M., Secco, L. F., Smith, R. C., Smith, N., Vivas, A. K., Tucker, D. L., Abbott, T. M. C., Avila, S., Bechtol, K., Bertin, E., Brooks, D., Buckley-Geer, E., Burke, D. L., Carnero Rosell, A., Carrasco Kind, M., Carretero, J., Castander, F. J., D'Andrea, C. B., da Costa, L. N., De Vicente, J., Desai, S., Doel, P., Flaugher, B., Fosalba, P., Gaztanaga, E., Gerdes, D. W., Goldstein, D. A., Gruen, D., Gruendl, R. A., Gutierrez, G., Hartley, W. G., Hollowood, D. L., Honscheid, K., Hoyle, B., James, D. J., Jeltema, T., Kent, S., Kuehn, K., Kuropatkin, N., Lahav, O., Lima, M., Maia, M. A. G., March, M., Menanteau, F., Miller, C. J., Miquel, R., Neilsen, E., Nord, B., Ogando, R. L. C., Plazas, A. A., Roodman, A., Sanchez, E., Scarpine, V., Schindler, R., Schubnell, M., Serrano, S., Sevilla-Noarbe, I., Smith, M., Sobreira, F., Suchyta, E., Swanson, M. E. C., Tarle, G., Thomas, D., Walker, A. R., Wester, W., Collaboration, DES, Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), DES, and Astronomy
Subjects: coalescence, 010504 meteorology & atmospheric sciences, media_common.quotation_subject, interferometer, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, localization, techniques: photometric, Binary black hole, star, surveys, Coincident, 0103 physical sciences, supernova, optical, LIGO, dark energy, 010303 astronomy & astrophysics, STFC, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, media_common, ONDAS GRAVITACIONAIS, Physics, astro-ph.HE, High Energy Astrophysical Phenomena (astro-ph.HE), Gravitational wave, gravitational radiation, RCUK, imaging, Astronomy and Astrophysics, Galaxy, Supernova, VIRGO, electromagnetic, gravitational waves, black hole: binary, Space and Planetary Science, Sky, Dark energy, galaxy, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], stars: black holes
Abstract: Binary black hole (BBH) mergers found by the LIGO and Virgo detectors are of immense scientific interest to the astrophysics community, but are considered unlikely to be sources of electromagnetic emission. To test whether they have rapidly fading optical counterparts, we used the Dark Energy Camera to perform an $i$-band search for the BBH merger GW170814, the first gravitational wave detected by three interferometers. The 87-deg$^2$ localization region (at 90\% confidence) centered in the Dark Energy Survey (DES) footprint enabled us to image 86\% of the probable sky area to a depth of $i\sim 23$ mag and provide the most comprehensive dataset to search for EM emission from BBH mergers. To identify candidates, we perform difference imaging with our search images and with templates from pre-existing DES images. The analysis strategy and selection requirements were designed to remove supernovae and to identify transients that decline in the first two epochs. We find two candidates, each of which is spatially coincident with a star or a high-redshift galaxy in the DES catalogs, and they are thus unlikely to be associated with GW170814. Our search finds no candidates associated with GW170814, disfavoring rapidly declining optical emission from BBH mergers brighter than $i\sim 23$ mag ($L_{\rm optical} \sim 5\times10^{41}$ erg/s) 1-2 days after coalescence. In terms of GW sky map coverage, this is the most complete search for optical counterparts to BBH mergers to date, Comment: 11 pages, 3 figures
Published: 2018
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9. Lattice Boltzmann simulation of mixtures with multicomponent van der Waals equation of state

Author: Alexander J. Wagner and Kent S. Ridl
Subjects: Physics, Van der Waals equation, Plane (geometry), Lattice Boltzmann methods, FOS: Physical sciences, Condensed Matter - Soft Condensed Matter, Computational Physics (physics.comp-ph), 01 natural sciences, 010305 fluids & plasmas, symbols.namesake, Volume (thermodynamics), 0103 physical sciences, symbols, Soft Condensed Matter (cond-mat.soft), Statistical physics, 010306 general physics, Constant (mathematics), Focus (optics), Physics - Computational Physics, Energy (signal processing), Phase diagram
Abstract: We developed a general framework for simulating multicomponent and multiphase systems using the lattice Boltzmann framework. Despite the fact that there is no restriction on the number of components in principle, in this article we focus an application to two-component mixtures, but we also demonstrate that the algorighm works for larger numbers of components. To validate our algorithm we separately minimized this underlying free energy to generate theoretical phase diagrams for mixtures of fluids with a van der Waals-like free energy. All the theoretical phase diagrams are well recovered by our lattice Boltzmann method., Comment: 18 pages 13 Figures
Published: 2018
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10. LOFAR Discovery of the Fastest-spinning Millisecond Pulsar in the Galactic Field

Author: Cees Bassa, V. I. Kondratiev, S. A. Sanidas, C. J. Clark, A. S. van Amesfoort, Elizabeth C. Ferrara, Jason W. T. Hessels, Scott M. Ransom, Paul S. Ray, Fernando Camilo, T. H. Burnett, Ziggy Pleunis, Kent S. Wood, Rene P. Breton, Peter F. Michelson, Tao Li, L. Nieder, N. V. Gusinskaia, and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: Physics, High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy and Astrophysics, LOFAR, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Light curve, Orbital period, 01 natural sciences, Luminosity, Neutron star, Pulsar, Space and Planetary Science, Millisecond pulsar, Globular cluster, 0103 physical sciences, Astrophysics - High Energy Astrophysical Phenomena, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: We report the discovery of PSR J0952$-$0607, a 707-Hz binary millisecond pulsar which is now the fastest-spinning neutron star known in the Galactic field (i.e., outside of a globular cluster). PSR J0952$-$0607 was found using LOFAR at a central observing frequency of 135 MHz, well below the 300 MHz to 3 GHz frequencies typically used in pulsar searches. The discovery is part of an ongoing LOFAR survey targeting unassociated Fermi Large Area Telescope $\gamma$-ray sources. PSR J0952$-$0607 is in a 6.42-hr orbit around a very low-mass companion ($M_\mathrm{c}\gtrsim0.02$ M$_\odot$) and we identify a strongly variable optical source, modulated at the orbital period of the pulsar, as the binary companion. The light curve of the companion varies by 1.6 mag from $r^\prime=22.2$ at maximum to $r^\prime>23.8$, indicating that it is irradiated by the pulsar wind. Swift observations place a 3-$\sigma$ upper limit on the $0.3-10$ keV X-ray luminosity of $L_X < 1.1 \times 10^{31}$ erg s$^{-1}$ (using the 0.97 kpc distance inferred from the dispersion measure). Though no eclipses of the radio pulsar are observed, the properties of the system classify it as a black widow binary. The radio pulsed spectrum of PSR J0952$-$0607, as determined through flux density measurements at 150 and 350 MHz, is extremely steep with $\alpha\sim-3$ (where $S \propto \nu^{\alpha}$). We discuss the growing evidence that the fastest-spinning radio pulsars have exceptionally steep radio spectra, as well as the prospects for finding more sources like PSR J0952$-$0607., Comment: 9 pages, 3 figures, 1 table, published in ApJ letters
Published: 2017
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11. The Electromagnetic Counterpart of the Binary Neutron Star Merger LIGO/Virgo GW170817. I. Discovery of the Optical Counterpart Using the Dark Energy Camera

Author: Soares-Santos, M., Holz, D.E., Annis, J., Chornock, R., Herner, K., Berger, E., Brout, D., Chen, H.-Y., Kessler, R., Sako, M., Allam, S., Tucker, DL., Butler, R. E., Palmese, A., Doctor, Z., Diehl, H.T., Frieman, J., Yanny, B., Lin, H., Scolnic, D., Cowperthwaite, P., Neilsen, E., Marriner, J., Kuropatkin, N., Hartley, W.G., Paz-Chinchón, F., Alexander, K.D., Balbinot, E., Blanchard, P., Brown, D.A., Carlin, J.L., Conselice, Christopher J., Cook, E.R., Drlica-Wagner, A., Drout, M.R., Durret, F., Eftekhari, T., Farr, B., Finley, D.A., Foley, R.J., Fong, W., Fryer, C.L., García-Bellido, J., Gill, M.S.S., Gruendl, R.A., Hanna, C., Kasen, D., Li, T.S., Lopes, P.A.A., Lourenço, A.C.C., Margutti, R., Marshall, J.L., Matheson, T., Medina, G.E., Metzger, B.D., Muñoz, R.R., Muir, J., Nicholl, M., Quataert, E., Rest, A., Sauseda, M., Schlegel, D.J., Secco, L.F., Sobreira, F., Stebbins, A., Villar, V.A., Vivas, K., Walker, A.R., Wester, W., Williams, P.K.G., Zenteno, A., Zhang, Y., Abbott, T.M.C., Abdalla, F.B., Banerji, M., Bechtol, K., Benoit-Lévy, A., Bertin, E., Brooks, D., Buckley-Geer, E., Burke, D.L., Rosell, A. Carnero, Kind, M. Carrasco, Carretero, J., Castander, F.J., Crocce, M., Cunha, C.E., D’Andrea, C.B., Costa, L.N. da, Davis, C., Desai, S., Dietrich, J.P., Doel, P., Eifler, T.F., Fernandez, E., Flaugher, B., Fosalba, P., Gaztanaga, E., Gerdes, D.W., Giannantonio, T., Goldstein, D.A., Gruen, D., Gschwend, J., Gutierrez, G., Honscheid, K., Jain, B., James, D.J., Jeltema, T., Johnson, M.W.G., Johnson, M.D., Kent, S., Krause, E., Kron, R., Kuehn, K., Kuhlmann, S., Lahav, O., Lima, M., Maia, M.A.G., March, M., McMahon, R.G., Menanteau, F., Miquel, R., Mohr, J.J., Nichol, R.C., Nord, B., Ogando, R.L C., Petravick, D., Plazas, A.A., Romer, A.K., Roodman, A., Rykoff, E.S., Sanchez, E., Scarpine, V., Schubnell, M., Sevilla-Noarbe, I., Smith, M., Smith, R.C., Suchyta, E., Swanson, M.E.C., Tarle, G., Thomas, D., Thomas, R.C., Troxel, M.A., Vikram, V., Wechsler, R.H., Weller, J., Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), DES, Dark Energy Camera GW-EM, Institut d'Astrophysique de Paris ( IAP ), and Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS )
Subjects: AST-1714498, neutron star: binary, close [binaries], [ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph], AST-1411763, Astrophysics, Kilonova, 01 natural sciences, localization, Luminosity, stars: neutron, neutron [stars], star, surveys, 0103 physical sciences, supernova, optical, luminosity, LIGO, dark energy, 010303 astronomy & astrophysics, STFC, LIGO Scientific Collaboration, QB, astro-ph.HE, Physics, binaries: close, 010308 nuclear & particles physics, Gravitational wave, background, nucleus, HEFCE, RCUK, Astronomy and Astrophysics, redshift, Redshift, messenger, Supernova, Neutron star, electromagnetic, VIRGO, gravitational waves, Space and Planetary Science, gravitational radiation: emission, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], catalogs
Abstract: We present the Dark Energy Camera (DECam) discovery of the optical counterpart of the first binary neutron star merger detected through gravitational wave emission, GW170817. Our observations commenced 10.5 hours post-merger, as soon as the localization region became accessible from Chile. We imaged 70 deg2 in the i and z bands, covering 93% of the initial integrated localization probability, to a depth necessary to identify likely optical counterparts (e.g., a kilonova). At 11.4 hours post-merger we detected a bright optical transient located 10.6′′ from the nucleus of NGC 4993 at redshift z = 0.0098, consistent (for H0=70\, km s−1 Mpc−1) with the distance of 40±8 Mpc reported by the LIGO Scientific Collaboration and the Virgo Collaboration (LVC). At detection the transient had magnitudes i ≈ 17.30 and z ≈ 17.45, and thus an absolute magnitude of Mi = −15.7, in the luminosity range expected for a kilonova. We identified 1,500 potential transient candidates. Applying simple selection criteria aimed at rejecting background events such as supernovae, we find the transient associated with NGC 4993 as the only remaining plausible counterpart, and reject chance coincidence at the 99.5% confidence level. We therefore conclude that the optical counterpart we have identified near NGC 4993 is associated with GW170817. This discovery ushers in the era of multi-messenger astronomy with gravitational waves, and demonstrates the power of DECam to identify the optical counterparts of gravitational-wave sources.
Published: 2017
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12. STROBE-X: X-Ray Timing and Spectroscopy on Dynamical Timescales from Microseconds to Years

Author: Silvia Zane, Keith C. Gendreau, Margarita Hernanz, Thomas J. Maccarone, Marco Feroci, C. Michelle Hui, Paul S. Ray, Kent S. Wood, Ron Remillard, Zaven Arzoumanian, P. A. Jenke, Søren Brandt, Deepto Chakrabarty, and Colleen A. Wilson-Hodge
Subjects: Stellar mass, Astrophysics::High Energy Astrophysical Phenomena, X-ray timing, FOS: Physical sciences, General Physics and Astronomy, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Missions, 010309 optics, General Relativity and Quantum Cosmology, Observatory, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Spectral resolution, Spectroscopy, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Compact objects, Astrophysics::Galaxy Astrophysics, Physics, X-ray spectroscopy, Supermassive black hole, Strong gravity, lcsh:QC1-999, Microsecond, Astrophysics - Instrumentation and Methods for Astrophysics, lcsh:Physics
Abstract: The Spectroscopic Time-Resolving Observatory for Broadband Energy X-rays (STROBE-X) probes strong gravity for stellar mass to supermassive black holes and ultradense matter with unprecedented effective area, high time-resolution, and good spectral resolution, while providing a powerful time-domain X-ray observatory., Accepted for Publication in Results in Physics
Published: 2017
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13. 3FHL: The Third Catalog of Hard Fermi-LAT Sources

Author: Igor V. Moskalenko, Lukasz Stawarz, Olaf Reimer, Seb. Funk, Diego F. Torres, Nicola Omodei, M. Razzano, M.-H. Grondin, Filippo D'Ammando, C. Favuzzi, M. Caragiulo, Alessandro Cuoco, E. J. Siskind, Jean Ballet, R. A. Cameron, F. Piron, Stefano Ciprini, J. M. Cohen, Alice K. Harding, M. N. Mazziotta, Seth Digel, Francesco Longo, R. Desiante, S. Cutini, A. A. Moiseev, Elliott D. Bloom, Jingcheng Li, Pascal Bruel, R. Buehler, F. Spada, D. Horan, Aaron Dominguez, Stefan Larsson, Marco Ajello, J. B. Thayer, F. Loparco, Peter F. Michelson, Marcello Giroletti, C. C. Cheung, N. Di Lalla, M. Di Mauro, Luca Baldini, M. Takahashi, T. Reposeur, Benoit Lott, Roger Blandford, P. Fusco, Sara Buson, D. J. Thompson, M. Palatiello, R. J. Britto, John W. Hewitt, F. de Palma, Sylvain Guiriec, R. Bonino, S. J. Fegan, A. Reimer, T. A. Porter, Matthew Wood, Johan Bregeon, Giacomo Principe, E. Orlando, Julie McEnery, Kent S. Wood, F. Gargano, Nestor Mirabal, P. Fortin, Soebur Razzaque, Luca Latronico, Giacomo Vianello, G. La Mura, Elizabeth C. Ferrara, J. G. Thayer, Regina Caputo, D. Costantin, D. Dumora, A. Chekhtman, P. Lubrano, W. B. Atwood, Ronaldo Bellazzini, Vaidehi S. Paliya, M. E. Monzani, J. S. Perkins, Nicola Giglietto, E. Hays, Anna Franckowiak, S. Rainò, Tsunefumi Mizuno, G. Chiaro, P. A. Caraveo, J. E. Grove, Yasushi Fukazawa, Persis S. Drell, J. D. Magill, Eric Charles, Manuel Meyer, D. J. Suson, Melissa Pesce-Rollins, I. A. Grenier, Dario Gasparrini, Warit Mitthumsiri, E. Cavazzuti, David H. Green, Gloria Spandre, P. Spinelli, L. Di Venere, M. Lemoine-Goumard, Francesco Giordano, D. Tak, Carmelo Sgrò, Riccardo Rando, D. Simone, E. Nuss, David Paneque, M. Kuss, T. Ohsugi, Eleonora Troja, M. Orienti, S. Maldera, F. Costanza, Eleonora Torresi, Elisabetta Bissaldi, Gudlaugur Johannesson, Lucas Guillemot, Guido Barbiellini, Paolo Giommi, Massimo Persic, T. Glanzman, Alberto Manfreda, Denis Bastieri, Claudia Cecchi, S. Kensei, Matteo Negro, A. Morselli, P. M. Saz Parkinson, Department of Physics and Astronomy [Clemson], Clemson University, Santa Cruz Institute for Particle Physics (SCIPP), University of California [Santa Cruz] (UCSC), University of California-University of California, University of Pisa - Università di Pisa, 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), Istituto Nazionale di Fisica Nucleare, Sezione di Trieste (INFN, Sezione di Trieste), Istituto Nazionale di Fisica Nucleare (INFN), Istituto Nazionale di Fisica Nucleare, Sezione di Padova (INFN, Sezione di Padova), Istituto Nazionale di Fisica Nucleare [Pisa] (INFN), Stanford University, Istituto Nazionale di Fisica Nucleare, Sezione di Torino (INFN, Sezione di Torino), 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), 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), Max-Planck-Institut für Physik (Werner-Heisenberg-Institut) (MPI-P), Istituto Nazionale di Fisica Nucleare, sezione di Bari (INFN, sezione di Bari), Agenzia Spaziale Italiana (ASI) Science Data Center, George Mason University [Fairfax], Universita degli Studi di Padova, Laboratoire de l'Accélérateur Linéaire (LAL), 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), Istituto Nazionale di Fisica Nucleare, Sezione di Torino, Istituto Nazionale di Astrofisica (INAF), Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, 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), Humboldt-Universität zu Berlin, Erlangen Centre for Astroparticle Physics (ECAP), Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), 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), Science Institute, University of Iceland, University of Iceland [Reykjavik], Hiroshima City University, Istituto Nazionale di Fisica Nucleare, Sezione di Perugia (INFN, Sezione di Perugia), Laboratoire d'interaction du rayonnement X avec la matière (LIXAM), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), NASA Goddard Space Flight Center (GSFC), Mahidol University [Bangkok], Hiroshima University, Istituto Nazionale di Fisica Nucleare, Sezione di Roma Tor Vergata (INFN, Sezione di Roma Tor Vergata), Istituto di Radioastronomia INAF, INAF - Osservatorio Astronomico di Trieste (OAT), PPM Group [University of Johannesburg], Department of Geology [University of Johannesburg], University of Johannesburg (UJ)-University of Johannesburg (UJ), NYCB Real-Time Computing Inc., Lattingtown, NYCB Real-Time Computing Inc. [Lattingtown], IEEC-CSIC, Universitat Autònoma de Barcelona (UAB), Istituto di Astrofisica Spaziale e Fisica cosmica - Bologna (IASF-Bo), Fermi-LAT Collaboration, Ajello, M., Atwood, W. B., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bellazzini, R., Bissaldi, E., Blandford, R. D., Bloom, E. D., Bonino, R., Bregeon, J., Britto, R. J., Bruel, P., Buehler, R., Buson, S., Cameron, R. A., Caputo, R., Caragiulo, M., Caraveo, P. A., Cavazzuti, E., Cecchi, C., Charles, E., Chekhtman, A., Cheung, C. C., Chiaro, G., Ciprini, S., Cohen, J. M., Costantin, D., Costanza, F., Cuoco, A., Cutini, S., D'Ammando, F., De Palma, F., Desiante, R., Digel, S. W., Di Lalla, N., Di Mauro, M., Di Venere, L., Domnguez, A., Drell, P. S., Dumora, D., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Fortin, P., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Green, D., Grenier, I. A., Grondin, M. -H., Grove, J. E., Guillemot, L., Guiriec, S., Harding, A. K., Hays, E., Hewitt, J. W., Horan, D., Jóhannesson, G., Kensei, S., Kuss, M., La Mura, G., Larsson, S., Latronico, L., Lemoine-Goumard, M., Li, J., Longo, F., Loparco, F., Lott, B., Lubrano, P., Magill, J. D., Maldera, S., Manfreda, A., Mazziotta, M. N., Mcenery, J. E., Meyer, M., Michelson, P. F., Mirabal, N., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monzani, M. E., Morselli, A., Moskalenko, I. V., Negro, M., Nuss, E., Ohsugi, T., Omodei, N., Orienti, M., Orlando, E., Palatiello, M., Paliya, V. S., Paneque, D., Perkins, J. S., Persic, M., Pesce-Rollins, M., Piron, F., Porter, T. A., Principe, G., Raino, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Reposeur, T., Saz Parkinson, P. M., Sgro, C., Simone, D., Siskind, E. J., Spada, F., Spandre, G., Spinelli, P., Stawarz, L., Suson, D. J., Takahashi, M., Tak, D., Thayer, J. G., Thayer, J. B., Thompson, D. J., Torres, D. F., Torresi, E., Troja, E., Vianello, G., Wood, K., Wood, M., National Institute for Nuclear Physics (INFN), Stanford University [Stanford], 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)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Humboldt Universität zu Berlin, 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, 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), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Universitat Autònoma de Barcelona [Barcelona] (UAB), ITA, University of California [Santa Cruz] (UC Santa Cruz), University of California (UC)-University of California (UC), 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), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Padova = University of Padua (Unipd), 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), Humboldt University Of Berlin, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), and University of Johannesburg [South Africa] (UJ)-University of Johannesburg [South Africa] (UJ)
Subjects: catalog, Astrophysics::High Energy Astrophysical Phenomena, catalogs, gamma rays: general, FOS: Physical sciences, Energy flux, Flux, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 7. Clean energy, 01 natural sciences, Astronomy and Astrophysics, Space and Planetary Science, law.invention, Telescope, law, 0103 physical sciences, catalogs – gamma rays: general, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, 010308 nuclear & particles physics, Astronomy, Galactic plane, Astronomy and Astrophysic, Redshift, Galaxy, Crab Nebula, [SDU]Sciences of the Universe [physics], ddc:520, Astrophysics - High Energy Astrophysical Phenomena, general [gamma rays], Fermi Gamma-ray Space Telescope
Abstract: We present a catalog of sources detected above 10 GeV by the Fermi Large Area Telescope (LAT) in the first 7 years of data using the Pass 8 event-level analysis. This is the Third Catalog of Hard Fermi-LAT Sources (3FHL), containing 1556 objects characterized in the 10 GeV - 2 TeV energy range. The sensitivity and angular resolution are improved by factors of 3 and 2 relative to the previous LAT catalog at the same energies (1FHL). The vast majority of detected sources (79%) are associated with extragalactic counterparts at other wavelengths, including 16 sources located at very high redshift ($z>2$). Eight percent of the sources have Galactic counterparts and 13% are unassociated (or associated with a source of unknown nature). The high-latitude sky and the Galactic plane are observed with a flux sensitivity of 4.4 to 9.5$\times 10^{-11}$ ph cm$^{-2}$ s$^{-1}$, respectively (this is approximately 0.5% and 1% of the Crab Nebula flux above 10 GeV). The catalog includes 214 new $\gamma$-ray sources. The substantial increase in the number of photons (more than 4 times relative to 1FHL and 10 times to 2FHL) also allows us to measure significant spectral curvature for 32 sources and find flux variability for 163 of them. Furthermore, we estimate that for the same flux limit of $10^{-12}$ erg cm$^{-2}$ s$^{-1}$, the energy range above 10 GeV has twice as many sources as above 50 GeV, highlighting the importance, for future Cherenkov telescopes, of lowering the energy threshold as much as possible., Comment: Accepted by ApJS. Contact authors: Alberto Dominguez, Marco Ajello, Benoit Lott, Sara Cutini, Pascal Fortin. The full FITS catalog will be made available at the FSSC: https://fermi.gsfc.nasa.gov/ssc/
Published: 2017
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14. The second catalog of flaring gamma-ray sources from the Fermi All-sky Variability Analysis

Author: L. Latronico, S. J. Fegan, M. Ackermann, Jean Ballet, C. Favuzzi, S. Maldera, F. Costanza, Roger Blandford, P. Bruel, M. E. Monzani, M. Razzano, Igor V. Moskalenko, Matteo Giomi, R. Bonino, Gino Tosti, Filippo D'Ammando, M. Di Mauro, Francesco Longo, Olaf Reimer, Dario Gasparrini, P. Fusco, Abhishek Desai, Nicola Omodei, K. Tanaka, J. B. Thayer, D. J. Thompson, Gudlaugur Johannesson, F. Spada, J. S. Perkins, Daniel Kocevski, Melissa Pesce-Rollins, C. C. Cheung, Vahé Petrosian, C. Cecchi, Giacomo Principe, D. Costantin, Janet Conrad, Lucas Guillemot, Luca Baldini, Johan Bregeon, W. B. Focke, F. Gargano, Frederic Piron, M. Takahashi, D. J. Suson, S. Abdollahi, T. A. Porter, R. A. Cameron, Marco Ajello, R. Buehler, A. Reimer, N. Di Lalla, I. A. Grenier, Sylvain Guiriec, Francesco Giordano, A. Franckowiak, M. Caragiulo, T. Ohsugi, Jingcheng Li, Monica Orienti, A. S. Johnson, A. Chekhtman, E. Cavazzuti, J. D. Magill, S. Buson, M. Kuss, Soebur Razzaque, Elizabeth Hays, Peter F. Michelson, Marcello Giroletti, David H. Green, G. Barbiellini, Matteo Negro, A. Morselli, Stefan Funk, Eleonora Troja, Giacomo Vianello, D. Horan, Andrea Albert, Elizabeth C. Ferrara, W. Mitthumsiri, M. N. Lovellette, G. La Mura, Nicola Giglietto, T. Glanzman, Gloria Spandre, Massimo Persic, P. Lubrano, Tsunefumi Mizuno, S. W. Digel, S. Cutini, G. Chiaro, M. N. Mazziotta, E. J. Siskind, Stefan Larsson, P. A. Caraveo, E. D. Bloom, J. E. Grove, Persis S. Drell, Yasushi Fukazawa, Ronaldo Bellazzini, P. Spinelli, Kent S. Wood, T. Jogler, F. de Palma, Eleonora Torresi, E. Nuss, L. Di Venere, Michael Mayer, Lukasz Stawarz, Carmelo Sgrò, Riccardo Rando, F. Loparco, D. Simone, David Paneque, Diego F. Torres, Elena Orlando, J. Becerra González, Elisabetta Bissaldi, Vaidehi S. Paliya, S. Rainò, Eugenio Bottacini, Alberto Manfreda, Denis Bastieri, B. Donaggio, S. Ciprini, R. Desiante, 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 Montpellier 2 - Sciences et Techniques (UM2), 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 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), 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 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)-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), ITA, 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), Abdollahi, S., Ackermann, M., Ajello, M., Albert, A., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Becerra Gonzalez, J., Bellazzini, R., Bissaldi, E., Blandford, R. D., Bloom, E. D., Bonino, R., Bottacini, E., Bregeon, J., Bruel, P., Buehler, R., Buson, S., Cameron, R. A., Caragiulo, M., Caraveo, P. A., Cavazzuti, E., Cecchi, C., Chekhtman, A., Cheung, C. C., Chiaro, G., Ciprini, S., Conrad, J., Costantin, D., Costanza, F., Cutini, S., D'Ammando, F., Palma, F. De, Desai, A., Desiante, R., Digel, S. W., Lalla, N. Di, Mauro, M. Di, Venere, L. Di, Donaggio, B., Drell, P. S., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Giglietto, N., Giomi, M., Giordano, F., Giroletti, M., Glanzman, T., Green, D., Grenier, I. A., Grove, J. E., Guillemot, L., Guiriec, S., Hays, E., Horan, D., Jogler, T., Jóhannesson, G., Johnson, A. 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., Mayer, M., Mazziotta, M. N., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monzani, M. E., Morselli, A., Moskalenko, I. V., Negro, M., Nuss, E., Ohsugi, T., Omodei, N., Orienti, M., Orlando, E., Paliya, V. S., Paneque, D., Perkins, J. S., Persic, M., Pesce-Rollins, M., Petrosian, V., Piron, F., Porter, T. A., Principe, G., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Sgrò, C., Simone, D., Siskind, E. J., Spada, F., Spandre, G., Spinelli, P., Stawarz, L., Suson, D. J., Takahashi, M., Tanaka, K., Thayer, J. B., Thompson, D. J., Torres, D. F., Torresi, E., Tosti, G., Troja, E., Vianello, G., Wood, K. S., Laboratoire AIM, Université Paris Diderot - Paris 7 ( UPD7 ) -Centre d'Etudes de Saclay, Université Montpellier 2 - Sciences et Techniques ( UM2 ), 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 de Physique et Chimie de l'Environnement et de l'Espace ( LPC2E ), Centre National de la Recherche Scientifique ( CNRS ) -Université d'Orléans ( UO ) -Institut national des sciences de l'Univers ( INSU - CNRS ), Unité Scientifique de la Station de Nançay ( USN ), and Institut national des sciences de l'Univers ( INSU - CNRS ) -Observatoire de Paris-Université d'Orléans ( UO ) -Centre National de la Recherche Scientifique ( CNRS )
Subjects: catalog, Active galactic nucleus, media_common.quotation_subject, [ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph], Astrophysics::High Energy Astrophysical Phenomena, galaxies: active, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Spectral line, law.invention, Telescope, photometric [techniques], techniques: photometric, Spitzer Space Telescope, law, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Variability, Blazar, 010303 astronomy & astrophysics, media_common, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), astroparticle physics, catalogs, gamma rays: general, Astronomy and Astrophysics, Space and Planetary Science, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Gamma ray, astroparticle physic, Astronomy and Astrophysic, Sky, [SDU]Sciences of the Universe [physics], active [galaxies], ddc:520, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - High Energy Astrophysical Phenomena, general [gamma rays], Fermi Gamma-ray Space Telescope
Abstract: We present the second catalog of flaring gamma-ray sources (2FAV) detected with the Fermi All-sky Variability Analysis (FAVA), a tool that blindly searches for transients over the entire sky observed by the Large Area Telescope (LAT) on board the \textit{Fermi} Gamma-ray Space Telescope. With respect to the first FAVA catalog, this catalog benefits from a larger data set, the latest LAT data release (Pass 8), as well as from an improved analysis that includes likelihood techniques for a more precise localization of the transients. Applying this analysis on the first 7.4 years of \textit{Fermi} observations, and in two separate energy bands 0.1$-$0.8 GeV and 0.8$-$300 GeV, a total of 4547 flares has been detected with a significance greater than $6\sigma$ (before trials), on the time scale of one week. Through spatial clustering of these flares, 518 variable gamma-ray sources are identified. Likely counterparts, based on positional coincidence, have been found for 441 sources, mostly among the blazar class of active galactic nuclei. For 77 2FAV sources, no likely gamma-ray counterpart has been found. For each source in the catalog, we provide the time, location, and spectrum of each flaring episode. Studying the spectra of the flares, we observe a harder-when-brighter behavior for flares associated with blazars, with the exception of BL Lac flares detected in the low-energy band. The photon indexes of the flares are never significantly smaller than 1.5. For a leptonic model, and under the assumption of isotropy, this limit suggests that the spectrum of the freshly accelerated electrons is never harder than $p\sim$2., Comment: Accepted for publication by The Astrophysical Journal Supplement. Online analysis results available at http://fermi.gsfc.nasa.gov/ssc/data/access/lat/FAVA/index.php . Corresponding authors: M. Giomi, R. Buehler, D. Kocevski, and M. Ajello
Published: 2016
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15. Cosmology from cosmic shear with Dark Energy Survey Science Verification data

Author: Abbott, T., Abdalla, F. B., Allam, S., Amara, A., Annis, J., Armstrong, R., Bacon, D., Banerji, M., Bauer, A. H., Baxter, E., Becker, M. R., Benoit-Lévy, A., Bernstein, R. A., Bernstein, G. M., Bertin, E., Blazek, J., Bonnett, C., Bridle, S. L., Brooks, D., Bruderer, C., Buckley-Geer, E., Burke, D. L., Busha, M. T., Capozzi, D., Carnero Rosell, A., Carrasco Kind, M., Carretero, J., Castander, F. J., Chang, C., Clampitt, J., Crocce, M., Cunha, C. E., D'Andrea, C. B., da Costa, L. N., Das, R., DePoy, D. L., Desai, S., Diehl, H. T., Dietrich, J. P., Dodelson, S., Doel, P., Drlica-Wagner, A., Efstathiou, G., Eifler, T. F., Erickson, B., Estrada, J., Evrard, A. E., Fausti Neto, A., Fernandez, E., Finley, D. A., Flaugher, B., Fosalba, P., Friedrich, O., Frieman, J., Gangkofner, C., Garcia-Bellido, J., Gaztanaga, E., Gerdes, D. W., Gruen, D., Gruendl, R. A., Gutierrez, G., Hartley, W., Hirsch, M., Honscheid, K., Huff, E. M., Jain, B., James, D. J., Jarvis, M., Kacprzak, T., Kent, S., Kirk, D., Krause, E., Kravtsov, A., Kuehn, K., Kuropatkin, N., Kwan, J., Lahav, O., Leistedt, B., Li, T. S., Lima, M., Lin, H., MacCrann, N., March, M., Marshall, J. L., Martini, P., McMahon, R. G., Melchior, P., Miller, C. J., Miquel, R., Mohr, J. J., Neilsen, E., Nichol, R. C., Nicola, A., Nord, B., Ogando, R., Palmese, A., Peiris, H. V., Plazas, A. A., Refregier, A., Roe, N., Romer, A. K., Roodman, A., Rowe, B., Rykoff, E. S., Sabiu, C., Sadeh, I., Sako, M., Samuroff, S., Sanchez, E., Sánchez, C., Seo, H., Sevilla-Noarbe, I., Sheldon, E., Smith, R. C., Soares-Santos, M., Sobreira, F., Suchyta, E., Swanson, M. E. C., Tarle, G., Thaler, J., Thomas, D., Troxel, M. A., Vikram, V., Walker, A. R., Wechsler, R. H., Weller, J., Zhang, Y., Zuntz, J., and Dark Energy Survey Collaboration, [Unknown]
Subjects: Cosmology and Gravitation, PARAMETER CONSTRAINTS, Dark matter, Cosmic microwave background, WEAK-LENSING TOMOGRAPHY, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Astronomy & Astrophysics, GALAXY ELLIPTICITIES, 01 natural sciences, Cosmology, Physics, Particles & Fields, symbols.namesake, PRECISION COSMOLOGY, MATTER POWER SPECTRUM, LARGE-SCALE STRUCTURE, 0103 physical sciences, Planck, 010303 astronomy & astrophysics, STFC, Weak gravitational lensing, QB, Photometric redshift, Physics, Science & Technology, 010308 nuclear & particles physics, RCUK, Astronomy, INTRINSIC ALIGNMENTS, Redshift, Physical Sciences, astro-ph.CO, Dark energy, symbols, COVARIANCE-MATRIX, BARYON ACOUSTIC-OSCILLATIONS, HUBBLE CONSTANT
Abstract: We present the first constraints on cosmology from the Dark Energy Survey (DES), using weak lensing measurements from the preliminary Science Verification (SV) data. We use 139 square degrees of SV data, which is less than 3% of the full DES survey area. Using cosmic shear 2-point measurements over three redshift bins we find σ8(Ωm/0.3)0.5=0.81±0.06 (68% confidence), after marginalizing over 7 systematics parameters and 3 other cosmological parameters. We examine the robustness of our results to the choice of data vector and systematics assumed, and find them to be stable. About 20% of our error bar comes from marginalizing over shear and photometric redshift calibration uncertainties. The current state-of-the-art cosmic shear measurements from CFHTLenS are mildly discrepant with the cosmological constraints from Planck CMB data; our results are consistent with both data sets. Our uncertainties are ∼30% larger than those from CFHTLenS when we carry out a comparable analysis of the two data sets, which we attribute largely to the lower number density of our shear catalogue. We investigate constraints on dark energy and find that, with this small fraction of the full survey, the DES SV constraints make negligible impact on the Planck constraints. The moderate disagreement between the CFHTLenS and Planck values of σ8(Ωm/0.3)0.5 is present regardless of the value of ω.
Published: 2016
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16. Detection of 16 gamma-ray pulsars through blind frequency searches using the Fermi LAT

Author: A. W. Borgland, W. B. Atwood, S. Germani, Grzegorz Madejski, Nicola Giglietto, A. P. Waite, Denis Bastieri, P. L. Nolan, A. De Luca, A. Reimer, M. N. Lovellette, Jeffrey D. Scargle, P. A. Caraveo, Persis S. Drell, C. Meurer, N. Kawai, R. A. Cameron, P. Fusco, Sylvain Guiriec, Francesco Longo, Carmelo Sgrò, Riccardo Rando, E. Hays, T. H. Burnett, Richard Dubois, Gino Tosti, R. E. Hughes, E. J. Siskind, Joel R. Primack, Claudia Cecchi, Johann Cohen-Tanugi, G.L. Godfrey, Nanda Rea, E. Nuss, P. Giommi, Matthew Kerr, S. J. Fegan, Takaaki Tanaka, Tadayuki Takahashi, W. Mitthumsiri, Paul S. Ray, David Paneque, M. Kuss, S. Rainò, M. S. Strickman, D. J. Thompson, Magnus Axelsson, V. Vasileiou, N. Vilchez, Jonathan F. Ormes, Kent S. Wood, Markus Ackermann, Jean Ballet, M. Lemoine-Goumard, Karen Watters, B. Lott, M. T. Wolff, C. Farnier, H. Tajima, M. Brigida, C. C. Cheung, T. Glanzman, A. Sander, R. Claus, F. Piron, Paul J. Wang, Stefano Ciprini, Jean-Luc Starck, J. M. Casandjian, G. A. Caliandro, A. Brez, Yasunobu Uchiyama, A. van Etten, J. P. Norris, T. Ylinen, Hiromitsu Takahashi, Morihiro Hayashida, Alice K. Harding, P. M. Saz Parkinson, A. Morselli, V. Vitale, A. Chekhtman, Tsunefumi Mizuno, David S. Smith, R. P. Johnson, T. Ohsugi, F. Gargano, Elliott D. Bloom, B. M. Baughman, Nicola Omodei, Luca Latronico, J. Bregeon, L. Guillemot, A. Y. Rodriguez, Brandon Anderson, M. Dormody, C. Monte, A. A. Abdo, E. Orlando, J. E. Grove, Yasushi Fukazawa, P. Spinelli, M. N. Mazziotta, F. Giordano, M. L. Kocian, Stefan Funk, T. A. Porter, Roger W. Romani, M.-H. Grondin, F. de Palma, J. G. Thayer, Seth Digel, Tyrel J. Johnson, A. Makeev, Dario Gasparrini, P. D. Smith, E. Do Couto E Silva, Brian L Winer, M. E. Monzani, P. Lubrano, Luca Baldini, Giovanni F. Bignami, H. F.W. Sadrozinski, Ronaldo Bellazzini, Emanuele Bonamente, M. Pierbattista, I. A. Grenier, Gudlaugur Johannesson, J. Lande, F. Loparco, M. Ziegler, Felix Ryde, A. De Angelis, Jürgen Knödlseder, Y. Hanabata, C. Favuzzi, Gloria Spandre, Guido Barbiellini, B. Giebels, Matthew G. Baring, A. Tramacere, S. Murgia, S. Ritz, Charles D. Dermer, D. Parent, Melissa Pesce-Rollins, O. Tibolla, D. J. Suson, B. Berenji, W. McConville, Pascal Bruel, W. N. Johnson, Peter F. Michelson, Hideaki Katagiri, T. Kamae, Igor V. Moskalenko, Olaf Reimer, Jan Conrad, Diego F. Torres, V. Pelassa, C. Gwon, Julie McEnery, Neil Gehrels, David Sánchez, Marco Ajello, L. Tibaldo, Jun Kataoka, Ö. Çelik, S. Cutini, M. Pepe, D. Dumora, James Chiang, Roger Blandford, M. Marelli, M. Razzano, L.S. Rochester, T. L. Usher, Keith Bechtol, T. Reposeur, Abdo, A. A., Ackermann, M., Ajello, M., Anderson, B., Atwood, W. B., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Baring, M. G., Bastieri, D., Baughman, B. M., Bechtol, K., Bellazzini, R., Berenji, B., Bignami, G. F., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Celik, O., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen Tanugi, J., Conrad, J., Cutini, S., Dermer, C. D., Angelis, A. d., Luca, A. d., Palma, F. d., Digel, S. W., Dormody, M., Silva, E. D. E., Drell, P. S., Dubois, R., Dumora, D., Farnier, C., Favuzzi, C., Fegan, S. J., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giommi, P., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Grondin, M. H., Grove, J. E., Guillemot, L., Guiriec, S., Gwon, C., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Hughes, R. E., Johannesson, G., Johnson, R. P., Johnson, T. J., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Kawai, N., Kerr, M., Knodlseder, J., Kocian, M. L., Kuss, M., Lande, J., Latronico, L., Lemoine Goumard, M., Longo, Francesco, Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Makeev, A., Marelli, M., Mazziotta, M. N., Mcconville, W., Mcenery, J. E., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Parent, D., Pelassa, V., Pepe, M., Pesce Rollins, M., Pierbattista, M., Piron, F., Porter, T. A., Primack, J. R., Raino, S., Rando, R., Ray, P. S., Razzano, M., Rea, N., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Rochester, L. S., Rodriguez, A. Y., Romani, R. W., Ryde, F., Sadrozinski, H. F. W., Sanchez, D., Sander, A., Parkinson, P. M. S., Scargle, J. D., Sgro, C., Siskind, E. J., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Starck, J. L., Strickman, M. S., Suson, D. J., Tajima, H., Takahashi, H., Takahashi, T., Tanaka, T., Thayer, J. G., Thompson, D. J., Tibaldo, L., Tibolla, O., Torres, D. F., Tosti, G., Tramacere, A., Uchiyama, Y., Usher, T. L., Etten, A. V., Vasileiou, V., Vilchez, N., Vitale, V., Waite, A. P., Wang, P., Watters, K., Winer, B. L., Wolff, M. T., Wood, K. S., Ylinen, T., Ziegler, M., 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 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 de Physique Théorique et Astroparticules (LPTA), 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), Centre d'étude spatiale des rayonnements (CESR), 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), Fermi-LAT, 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), 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-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-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), 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)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::High Energy Astrophysical Phenomena, Fermi satellite, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, High Energy Gamma-ray Astronomy, Pulsar, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010306 general physics, Supernova remnant, 010303 astronomy & astrophysics, Pulsars, Astrophysics::Galaxy Astrophysics, Physics, Multidisciplinary, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Gamma ray, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astrophysics - Astrophysics of Galaxies, Neutron star, Stars, Supernova, Astrophysics - High Energy Astrophysical Phenomena, Fermi Gamma-ray Space Telescope, X-ray pulsar
Abstract: Pulsars are rapidly-rotating, highly-magnetized neutron stars emitting radiation across the electromagnetic spectrum. Although there are more than 1800 known radio pulsars, until recently, only seven were observed to pulse in gamma rays and these were all discovered at other wavelengths. The Fermi Large Area Telescope makes it possible to pinpoint neutron stars through their gamma-ray pulsations. We report the detection of 16 gamma-ray pulsars in blind frequency searches using the LAT. Most of these pulsars are coincident with previously unidentified gamma-ray sources, and many are associated with supernova remnants. Direct detection of gamma-ray pulsars enables studies of emission mechanisms, population statistics and the energetics of pulsar wind nebulae and supernova remnants., Comment: Corresponding authors: Michael Dormody, Paul S. Ray, Pablo M. Saz Parkinson, Marcus Ziegler
Published: 2009
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17. Detection of high-energy gamma-ray emission from the globular cluster 47 Tucanae with Fermi

Author: I. A. Grenier, Marco Ajello, Francesco Longo, J. B. Thayer, T. H. Burnett, M. Ziegler, A. Sander, N. Kawai, Yasunobu Uchiyama, L. Tibaldo, V. Vasileiou, Kent S. Wood, C. Meurer, Luca Latronico, P. Wang, Hartmut Sadrozinski, Gloria Spandre, Denis Bastieri, N.A. Webb, Alessandro Brez, Gino Tosti, C. C. Cheung, Igor V. Moskalenko, Luca Baldini, R. E. Hughes, Emanuele Bonamente, A. Chekhtman, T. L. Usher, J. Lande, Sylvain Guiriec, Olaf Reimer, D. Horan, Jean Ballet, A. Y. Rodriguez, V. Pelassa, M. Pierbattista, R. Dubois, J. M. Casandjian, P. L. Nolan, L. Guillemot, D. J. Thompson, W. B. Focke, Stefano Ciprini, C. Farnier, B. M. Baughman, Diego F. Torres, P. Spinelli, P. D. Smith, C. Favuzzi, M. Razzano, S. Rainò, Tsunefumi Mizuno, Eric Charles, P. M. Saz Parkinson, C. Monte, T. Ohsugi, D. Parent, S. Murgia, B. Lott, Julie McEnery, Neil Gehrels, Hiromitsu Takahashi, David Sánchez, Elliott D. Bloom, W. B. Atwood, D. J. Suson, F. Piron, Pascal Bruel, Ö. Çelik, A. S. Johnson, S. Cutini, Francesco Giordano, T. Kamae, T. Glanzman, Nicola Giglietto, Jürgen Knödlseder, Nicola Omodei, M. Pepe, W. N. Johnson, W. McConville, Claudia Cecchi, Y. Hanabata, Randall P. Johnson, Carmelo Sgrò, Riccardo Rando, Alice K. Harding, Dario Gasparrini, Peter F. Michelson, M. N. Mazziotta, J. G. Thayer, A. Tramacere, James Chiang, A. A. Abdo, E. Orlando, P. Lubrano, B. Giebels, F. Gargano, Roger Blandford, Roger W. Romani, E. Nuss, G. Godfrey, Sylvain Chaty, M. N. Lovellette, Jean-Luc Starck, T. Reposeur, P. A. Caraveo, J. E. Grove, David Paneque, Takaaki Tanaka, D. Dumora, J. P. Norris, Hideaki Katagiri, A. Morselli, Persis S. Drell, Yasushi Fukazawa, Johann Cohen-Tanugi, Nanda Rea, A. W. Borgland, M. Kuss, J. F. Ormes, M. S. Strickman, V. Vitale, M. Roth, J. Bregeon, E. Hays, Seth Digel, M. Brigida, F. de Palma, F. Kuehn, E. Do Couto E Silva, T. Ylinen, J. H. Panetta, Magnus Axelsson, M. Lemoine-Goumard, Brian L Winer, N. Vilchez, Hiroyasu Tajima, Tyrel J. Johnson, T. A. Porter, Jan Conrad, Markus Ackermann, R. A. Cameron, Morihiro Hayashida, A. A. Moiseev, Keith Bechtol, M. Dormody, R. Claus, P. Fusco, F. Loparco, Gudlaugur Johannesson, A. Makeev, W. Mitthumsiri, Matthew Kerr, Felix Ryde, M. E. Monzani, G. A. Caliandro, S. J. Fegan, Guido Barbiellini, M. Frailis, L. S. Rochester, B. Berenji, Ronaldo Bellazzini, S. Ritz, Charles D. Dermer, David Smith, S. Germani, A. Reimer, Abdo, A. A., Ackermann, M., Ajello, M., Atwood, W. B., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Baughman, B. M., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Celik, O., Charles, E., Chaty, S., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen Tanugi, J., Conrad, J., Cutini, S., Dermer, C. D., Palma, F. d., Digel, S. W., Dormody, M., Silva, E. D. E., Drell, P. S., Dubois, R., Dumora, D., Farnier, C., Favuzzi, C., Fegan, S. J., Focke, W. B., Frailis, M., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guillemot, L., Guiriec, S., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Horan, D., Hughes, R. E., Johannesson, G., Johnson, A. S., Johnson, R. P., Johnson, T. J., Johnson, W. N., Kamae, T., Katagiri, H., Kawai, N., Kerr, M., Knodlseder, J., Kuehn, F., Kuss, M., Lande, J., Latronico, L., Lemoine Goumard, M., Longo, Francesco, Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Makeev, A., Mazziotta, M. N., Mcconville, W., Mcenery, J. E., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Pierbattista, M., Piron, F., Porter, T. A., Raino, S., Rando, R., Razzano, M., Rea, N., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Rochester, L. S., Rodriguez, A. Y., Romani, R. W., Roth, M., Ryde, F., Sadrozinski, H. F. W., Sanchez, D., Sander, A., Parkinson, P. M. S., Sgro, C., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Starck, J. L., Strickman, M. S., Suson, D. J., Tajima, H., Takahashi, H., Tanaka, T., Thayer, J. B., Thayer, J. G., Thompson, D. J., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Uchiyama, Y., Usher, T. L., Vasileiou, V., Vilchez, N., Vitale, V., Wang, P., Webb, N., Winer, B. L., Wood, K. S., Ylinen, T., Ziegler, M., 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), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Théorique et Astroparticules (LPTA), 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-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-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), 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)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, High Energy Astrophys. & Astropart. Phys (API, FNWI), 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 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), and 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)
Subjects: [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::High Energy Astrophysical Phenomena, Population, Fermi satellite, Astrophysics, 01 natural sciences, High Energy Gamma-ray Astronomy, Globular Clusters, Luminosity, Pulsar, Millisecond pulsar, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, education, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, education.field_of_study, Multidisciplinary, 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Neutron star, Star cluster, Globular cluster, Fermi Gamma-ray Space Telescope
Abstract: Gamma-Ray Pulsar Bonanza Most of the pulsars we know about were detected through their radio emission; a few are known to pulse gamma rays but were first detected at other wavelengths (see the Perspective by Halpern ). Using the Fermi Gamma-Ray Space Telescope, Abdo et al. (p. 840 , published online 2 July; see the cover) report the detection of 16 previously unknown pulsars based on their gamma-ray emission alone. Thirteen of these coincide with previously unidentified gamma-ray sources, solving the 30-year-old mystery of their identities. Pulsars are fast-rotating neutron stars. With time they slow down and cease to radiate; however, if they are in a binary system, they can have their spin rates increased by mass transfer from their companion stars, starting a new life as millisecond pulsars. In another study, Abdo et al. (p. 845 ) report the detection of gamma-ray emission from the globular cluster 47 Tucanae, which is coming from an ensemble of millisecond pulsars in the cluster's core. The data imply that there are up to 60 millisecond pulsars in 47 Tucanae, twice as many as predicted by radio observations. In a further companion study, Abdo et al. (p. 848 , published online 2 July) searched Fermi Large Area Telescope data for pulsations from all known millisecond pulsars outside of stellar clusters, finding gamma-ray pulsations for eight of them. Their properties resemble those of other gamma-ray pulsars, suggesting that they share the same basic emission mechanism. Indeed, both sets of pulsars favor emission models in which the gamma rays are produced in the outer magnetosphere of the neutron star.
Published: 2009
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18. Possible Magnetic Activity in the Low-Mass X-Ray Binary EXO 0748-676

Author: Kent S. Wood, Michael T. Wolff, and Paul S. Ray
Subjects: Physics, endocrine system, Drop (liquid), Astrophysics (astro-ph), X-ray binary, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Plasma, Light curve, Space and Planetary Science, Binary system, Absorption (electromagnetic radiation), Low Mass, Eclipse
Abstract: We report evidence of magnetic activity associated with the secondary star in the EXO 0748-676 low mass X-ray binary system. An analysis of a sequence of five consecutive X-ray eclipses observed during December 2003 with the RXTE satellite brings out a feature occurring during ingress we interpret as the X-ray photoelectric absorption shadow, as seen by an observer at Earth, of a plasma structure suspended above the surface of the secondary star. The light curve feature consists of an initial drop in count rate to near zero (the absorption shadow) with a very short rebound to a significant fraction of the pre-ingress count rate and then a final plunge to totality over a total time scale of ~25 s. The ingress feature persists for at least 5 consecutive orbital periods (a total of ~19 hr), and possibly up to 5 days in our data. Our data also show significant post-egress dipping during this eclipse sequence, unusual for this source, indicating possible secondary star mass ejection during this episode., Accepted by Astrophysical Journal Letters; 11 Pages including 3 figures and 1 table
Published: 2007
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19. Standing Shock Instability in Advection-Dominated Accretion Flows

Author: Joy Putney, Michael T. Wolff, Truong Le, Kent S. Wood, and Peter A. Becker
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Supermassive black hole, Angular momentum, Shock (fluid dynamics), Accretion (meteorology), 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy and Astrophysics, Radius, Astrophysics, Parameter space, 01 natural sciences, Instability, Astrophysics - Astrophysics of Galaxies, Acceleration, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Astrophysics - High Energy Astrophysical Phenomena, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: Depending on the values of the energy and angular momentum per unit mass in the gas supplied at large radii, inviscid advection-dominated accretion flows can display velocity profiles with either preshock deceleration or preshock acceleration. Nakayama has shown that these two types of flow configurations are expected to have different stability properties. By employing the Chevalier \& Imamura linearization method and the Nakayama instability boundary conditions, we discover that there are regions of parameter space where disks/shocks with outflows can be stable or unstable. In regions of instability, we find that preshock deceleration is always unstable to the zeroth mode with zero frequency of oscillation, but is always stable to the fundamental mode and overtones. Furthermore, we also find that preshock acceleration is always unstable to the zeroth mode and that the fundamental mode and overtones become increasingly less stable as the shock location moves away from the horizon when the disk half-height expands above $\sim 12$ gravitational radii at the shock radius. In regions of stability, we demonstrate the zeroth mode to be stable for the velocity profiles that exhibit preshock acceleration and deceleration. Moreover, for models that are linearly unstable, our model suggests the possible existence of quasi-periodic oscillations (QPOs) with ratios 2:3 and 3:5. These ratios are believed to occur in stellar and supermassive black hole candidates, for example, in GRS 1915+105 and Sgr A*, respectively. We expect that similar QPO ratios also exist in regions of stable shocks., accepted for publication in ApJ. The paper contains 42 pages and 54 figures (v1); last revised 25 Mar. 2016 (this version, v2))
Published: 2015

20. The Transient Accereting X-Ray Pulsar XTE J1946+274: Stability of the X-Ray Properties at Low Flux and Updated Orbital Solution

Author: Yukikatsu Terada, Sebastian Falkner, Richard E. Rothschild, Wataru Iwakiri, Isabel Caballero, Dmitry Klochkov, Katja Pottschmidt, Teruaki Enoto, Mark H. Finger, Kent S. Wood, Diana M. Marcu-Cheatham, P. Jenke, I. Kreykenbohm, Victoria Grinberg, Paul B. Hemphill, Felix Fürst, Peter A. Becker, Michael T. Wolff, Joern Wilms, Sebastian Müller, Matthias Kühnel, and Colleen A. Wilson-Hodge
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Flux, Astronomy and Astrophysics, Astrophysics, Spectral line, Luminosity, Neutron star, Pulsar, Space and Planetary Science, Emission spectrum, Astrophysics - High Energy Astrophysical Phenomena, X-ray pulsar, Line (formation)
Abstract: We present a timing and spectral analysis of the X-ray pulsar XTE J1946+274 observed with Suzaku during an outburst decline in 2010 October and compare with previous results. XTE J1946+274 is a transient X-ray binary consisting of a Be-type star and a neutron star with a 15.75 s pulse period in a 172 d orbit with 2-3 outbursts per orbit during phases of activity. We improve the orbital solution using data from multiple instruments. The X-ray spectrum can be described by an absorbed Fermi-Dirac cutoff power law model along with a narrow Fe K line at 6.4 keV and a weak Cyclotron Resonance Scattering Feature (CRSF) at ~35 keV. The Suzaku data are consistent with the previously observed continuum flux versus iron line flux correlation expected from fluorescence emission along the line of sight. However, the observed iron line flux is slightly higher, indicating the possibility of a higher iron abundance or the presence of non-uniform material. We argue that the source most likely has only been observed in the subcritical (non-radiation dominated) state since its pulse profile is stable over all observed luminosities and the energy of the CRSF is approximately the same at the highest (~$5 \times 10^{37} $erg s$^{-1}$) and lowest (~$5 \times 10^{36} $erg s$^{-1}$) observed 3-60 keV luminosities., Accepted, 13 pages, 8 figures
Published: 2015

21. High energy gamma-ray emission from PSR B1259-63 SS 2883 during 2014 and 2010 periastron passages

Author: Kent S. Wood, Diego F. Torres, C. C. Cheung, Jian Li, and G. Andrea Caliandro
Subjects: Physics, High energy, Gamma ray, Astrophysics
Published: 2015
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22. Eight new Milky Way companions discovered in first-year Dark Energy Survey Data

Author: Des, The Collaboration, Bechtol, K., Drlica-Wagner, A., Balbinot, E., Pieres, A., Simon, J. D., Yanny, B., Santiago, B., Wechsler, R. H., Frieman, J., Walker, A. R., Williams, P., Rozo, E., Rykoff, E. S., Queiroz, A., Luque, E., Benoit-Levy, A., Tucker, D., Sevilla, I., Gruendl, R. A., Da Costa, L. N., Fausti Neto, A., Maia, M. A. G., Abbott, T., Allam, S., Armstrong, R., Bauer, A. H., Bernstein, G. M., Bernstein, R. A., Bertin, E., Brooks, D., Buckley-Geer, E., Burke, D. L., Carnero Rosell, A., Castander, F. J., Covarrubias, R., D Andrea, C. B., Depoy, D. L., Desai, S., Diehl, H. T., Eifler, T. F., Estrada, J., August Evrard, Fernandez, E., Finley, D. A., Flaugher, B., Gaztanaga, E., Gerdes, D., Girardi, L., Gladders, M., Gruen, D., Gutierrez, G., Hao, J., Honscheid, K., Jain, B., James, D., Kent, S., Kron, R., Kuehn, K., Kuropatkin, N., Lahav, O., Li, T. S., Lin, H., Makler, M., March, M., Marshall, J., Martini, P., Merritt, K. W., Miller, C., Miquel, R., Mohr, J., Neilsen, E., Nichol, R., Nord, B., Ogando, R., Peoples, J., Petravick, D., Plazas, A. A., Romer, A. K., Roodman, A., Sako, M., Sanchez, E., Scarpine, V., Schubnell, M., Smith, R. C., Soares-Santos, M., Sobreira, F., Suchyta, E., Swanson, M. E. C., Tarle, G., Thaler, J., Thomas, D., Wester, W., and Zuntz, J.
Subjects: Cosmology and Gravitation, Stellar population, dwarf [galaxies], Milky Way, astro-ph.GA, FOS: Physical sciences, Astrophysics, Galaxia, Astrophysics::Cosmology and Extragalactic Astrophysics, Satellite galaxy, Astrophysics::Solar and Stellar Astrophysics, Eridanus, STFC, Astrophysics::Galaxy Astrophysics, Luminosity function (astronomy), QB, Physics, Aglomerados de galaxias, RCUK, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Galaxy, Stars, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Dark energy, Local Group, Astrophysics::Earth and Planetary Astrophysics
Abstract: We report the discovery of eight new Milky Way companions in ~1,800 deg^2 of optical imaging data collected during the first year of the Dark Energy Survey (DES). Each system is identified as a statistically significant over-density of individual stars consistent with the expected isochrone and luminosity function of an old and metal-poor stellar population. The objects span a wide range of absolute magnitudes (M_V from -2.2 mag to -7.4 mag), physical sizes (10 pc to 170 pc), and heliocentric distances (30 kpc to 330 kpc). Based on the low surface brightnesses, large physical sizes, and/or large Galactocentric distances of these objects, several are likely to be new ultra-faint satellite galaxies of the Milky Way and/or Magellanic Clouds. We introduce a likelihood-based algorithm to search for and characterize stellar over-densities, as well as identify stars with high satellite membership probabilities. We also present completeness estimates for detecting ultra-faint galaxies of varying luminosities, sizes, and heliocentric distances in the first-year DES data., 33 pages, 12 figures, 3 tables. Accepted for publication in ApJ. Readers may be interested in the concurrent work by Koposov, Belokurov, Torrealba, & Evans (http://arxiv.org/abs/1503.02079). Indirect dark matter search results are presented in Drlica-Wagner, Albert, Bechtol, Wood, Strigari, et al. (The LAT and DES Collaborations, http://arxiv.org/abs/1503.02632)
Published: 2015
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23. Looking into the Theory of Pulsar Accretion: The Case of XTE J1946+274

Author: Carlo Ferrigno, D. M. Marcu, Kent S. Wood, Amy M. Gottlieb, Joern Wilms, Michael T. Wolff, Katja Pottschmidt, and Peter A. Becker
Subjects: Physics, Pulsar, Astrophysics, Accretion (finance)
Published: 2015
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24. Spacecraft Navigation Using X-Ray Pulsars

Author: Darryll J. Pines, Michael T. Wolff, Suneel I. Sheikh, Paul S. Ray, Kent S. Wood, and M. N. Lovellette
Subjects: Physics, Spacecraft, business.industry, Crab Pulsar, Astrophysics::High Energy Astrophysical Phenomena, Applied Mathematics, Aerospace Engineering, Astronomy, NASA Deep Space Network, Astrophysics, Atomic clock, Neutron star, Stars, Pulsar, Space and Planetary Science, Control and Systems Engineering, Position (vector), Electrical and Electronic Engineering, business
Abstract: The feasibility of determining spacecraft time and position using x-ray pulsars is explored. Pulsars are rapidly rotating neutron stars that generate pulsed electromagnetic radiation. A detailed analysis of eight x-ray pulsars is presented to quantify expected spacecraft position accuracy based on described pulsar properties, detector parameters, and pulsar observation times. In addition, a time transformation equation is developed to provide comparisons of measured and predicted pulse time of arrival for accurate time and position determination. This model is used in a new pulsar navigation approach that provides corrections to estimated spacecraft position. This approach is evaluated using recorded flight data obtained from the unconventional stellar aspect x-ray timing experiment. Results from these data provide first demonstration of position determination using the Crab pulsar.
Published: 2006
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25. Discovery of Psr J1227-4853: A Transition from a Low-mass X-Ray Binary to a Redback Millisecond Pulsar

Author: Jason W. T. Hessels, Jayaram N. Chengalur, Kent S. Wood, Michael T. Wolff, Ben Stappers, Alice K. Harding, Cees Bassa, Jayanta Roy, Tyrel J. Johnson, Elizabeth C. Ferrara, Paul S. Ray, Julia Deneva, Fernando Camilo, Evan Keane, Bhaswati Bhattacharyya, and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: Orbital elements, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Giant Metrewave Radio Telescope, X-ray binary, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Radio telescope, Pulsar, Space and Planetary Science, Millisecond pulsar, Binary star, Astrophysics - High Energy Astrophysical Phenomena, Fermi Gamma-ray Space Telescope
Abstract: XSS J12270-4859 is an X-ray binary associated with the Fermi LAT gamma-ray source 1FGL J1227.9-4852. In 2012 December, this source underwent a transition where the X-ray and optical luminosity dropped and the spectral signatures of an accretion disc disappeared. We report the discovery of a 1.69 millisecond pulsar (MSP), PSR J1227-4853, at a dispersion measure of 43.4 pc cm$^{-3}$ associated with this source, using the GMRT at 607 MHz. This demonstrates that, post-transition, the system hosts an active radio MSP. This is the third system after PSR J1023+0038 and PSR J1824-2452I showing evidence of state switching between radio MSP and low-mass X-ray binary (LMXB) states. We report timing observations of PSR J1227-4853 with the GMRT and Parkes, which give a precise determination of the rotational and orbital parameters of the system. The companion mass measurement of 0.17 to 0.46 M$_{sun}$ suggests that this is a redback system. PSR J1227-4853 is eclipsed for about 40% of its orbit at 607 MHz; with additional short-duration eclipses at all orbital phases. We also find that the pulsar is very energetic, with a spin-down luminosity of ~ 10$^{35}$ erg s$^{-1}$. We report simultaneous imaging and timing observations with the GMRT, which suggests that eclipses are caused by absorption, rather than dispersion smearing or scattering., Comment: 16 pages, 3 figures, accepted for publication in ApJ Letters
Published: 2015
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26. Why Is It Difficult to Detect a Millisecond Pulsar in Neutron Star X-Ray Binaries?

Author: Kent S. Wood, Wei Cui, and Lev Titarchuk
Subjects: Physics, Accretion, Millisecond, Photon, Scattering, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), FOS: Physical sciences, Accretion Disks, Stars: Pulsars: Individual: Alphanumeric: SAX J1808.4-3658, Stars: Neutron, X-Rays: Stars, Astronomy and Astrophysics, Astrophysics, Omega, Neutron star, Amplitude, Space and Planetary Science, Millisecond pulsar, Optical depth (astrophysics)
Abstract: We explain why it is possible to detect directly X-ray emission from near the surface of the neutron star (NS) in SAX J1808.4-3658 but not in most other low-mass X-ray binaries (LMXBs), with the exception that emission from the surface can be seen during bursts events. We show that the X-ray emission from SAX J1808.4-3658 mostly originates in the Comptonization process in a relatively optical thin hot region (with an optical depth $\tau_0$ around 4 and temperature is around 20 keV). Such a transparent region does not prevent us from detecting coherent X-ray pulsation due to hot spots on the NS surface. When the characteristic scattering time in the region is of order of inverse rotational frequency omega or higher then the amplitude of the harmonic oscillation decays exponentially with (tau_0 x omega). We give a precise model for the loss of modulation, such suppression of the QPO amplitude due to scattering can explain the disappearance of kHz QPOs with increasing QPO frequency. We also formulate general conditions under which the millisecond X-ray pulsation can be detected in LMXBs. We demonstrate that the observed soft phase lag of the pulsed emission is a result of the downscattering of the hard X-ray photons in the relatively cold material near the NS surface. In the framework of this downscattering model we propose a method to determine the atmosphere density in that region from soft-lag measurements., Comment: 9 pages, 3 figures, accepted for publication in Ap. J. Letters
Published: 2002
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27. Eclipse Timings of the Low‐Mass X‐Ray Binary EXO 0748−676. III. Orbital Period Jitter Observed with the Unconventional Stellar Aspect Experiment and theRossi X‐Ray Timing Explorer

Author: Paul S. Ray, Reba M. Bandyopadhyay, Paul Hertz, Michael T. Wolff, and Kent S. Wood
Subjects: Physics, Observational error, Space and Planetary Science, X-ray binary, Binary number, Astronomy, Astronomy and Astrophysics, Astrophysics, Ephemeris, Orbital period, Low Mass, Eclipse, Jitter
Abstract: We present seven eclipse timings of the low-mass X-ray binary (LMXB) EXO 0748-676 obtained with the Unconventional Stellar Aspect (USA) Experiment during 1999-2000, as well as 122 eclipse timings obtained with the Rossi X-Ray Timing Explorer (RXTE) during 1996-2000. According to our analysis, the mean orbital period has increased by ~8 ms between the pre-RXTE era (1985-1990) and the RXTE/USA era (1996-2000). This corresponds to an orbital period derivative of Porb/orb ~ 2 × 107 yr. However, neither a constant orbital period derivative nor any other simple ephemeris provides an acceptable fit to the data; individual timings of eclipse centers have residuals of up to 15 or more seconds away from our derived smooth ephemerides. When we consider all published eclipse timing data, including those presented here, a model that includes observational measurement error, cumulative period jitter, and underlying period evolution is found to be consistent with the timing data. We discuss several physical mechanisms for LMXB orbital evolution in an effort to account for the change in orbital period and the observed intrinsic jitter in the mideclipse times.
Published: 2002
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28. Observation of X‐Ray Variability in the BL Lacertae Object 1ES 1959+65

Author: G. Shabad, G. Godfrey, Michael T. Wolff, W. B. Focke, Kent S. Wood, Pablo M. Saz Parkinson, Paul Hertz, Reba M. Bandyopadhyay, E. D. Bloom, Greg Madejski, K. T. Reilly, B. Giebels, Jeffrey D. Scargle, M. N. Lovellette, Daryl J. Yentis, Paul S. Ray, Michael P. Kowalski, and Gilbert G. Fritz
Subjects: Physics, Line-of-sight, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), FOS: Physical sciences, Flux, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Synchrotron, law.invention, symbols.namesake, Relativistic beaming, Space and Planetary Science, law, symbols, Blazar, Doppler effect, Flare, BL Lac object
Abstract: This paper reports X-ray spectral observations of a relatively nearby z = 0.048 BL Lacertae (BL Lac) object 1ES1959+650, which is a potential TeV emitter. The observations include 31 short pointings made by the Unconventional Stellar Aspect (USA) Experiment on board the Advanced Research and Global Observation Satellite (ARGOS), and 17 pointings by the PCA on board the Rossi X-ray Timing Explorer (RXTE). Most of these observations were spaced by less than 1 day. \es was detected by the ARGOS USA detector in the range 1-16 keV, and by the PCA in the 2-16 keV range but at different times. During the closely spaced RXTE observations beginning on 2000 July 28, an ending of one flare and a start of another are visible, associated with spectral changes, where the photon index Gamma ranges between ~ 1.4 and 1.7, and the spectrum is harder when the source is brighter. This implies that 1ES1959 is an XBL-type blazar, with the X-ray emission likely to originate via the synchrotron process. The USA observations reveal another flare that peaked on 2000 November 14 and doubled the flux within a few days, again associated with spectral changes of the same form. The spectral variability correlated with the flux and timing characteristics of this object that are similar to those of other nearby BL Lacs, and suggest relativistic beaming with a Doppler factor delta > 1.6 and magnetic fields of the order of a few mG. We also suggest that the steady component of the X-ray emission -- present in this object as well as in other XBLs -- may be due to the large-scale relativistic jet (such as measured by Chandra in many radio-loud AGN), but pointing very closely to our line of sight., To appear in ApJ June 1, 2002 issue
Published: 2002
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29. USA Experiment Observation of Spectral and Timing Evolution during the 2000 Outburst of XTE J1550−564

Author: Gilbert G. Fritz, R. M. Bandyopadhyay, W. B. Focke, B. Giebels, G. Godfrey, Paul S. Ray, Kent S. Wood, and D. J. Yentis, K. T. Reilly, Paul Hertz, Michael P. Kowalski, andJeffrey D. Scargle, Elliott D. Bloom, P. M. Saz Parkinson, Michael T. Wolff, M. N. Lovellette, and and G. Shabad
Subjects: Physics, Accretion (meteorology), Hardness ratio, Oscillation, Astrophysics::High Energy Astrophysical Phenomena, Astronomy, Flux, Astronomy and Astrophysics, Astrophysics, On board, Amplitude, Space and Planetary Science, Satellite, Clockwise
Abstract: We report on timing and spectral observations of the 2000 outburst of XTE J1550-564 made by the Unconventional Stellar Aspect (USA) experiment on board the Advanced Research and Global Observation Satellite (ARGOS). We observe a low-frequency quasi-periodic oscillation with a centroid frequency that tends to increase with increasing flux and a fractional rms amplitude that is correlated with the hardness ratio. Several high-frequency quasi-periodic oscillations were detected by Rossi X-Ray Timing Explorer during periods where the low-frequency quasi-periodic oscillation was seen to be weakening or not detectable at all. The evolution of the hardness ratio (4-16 keV/1-4 keV) with time and source flux is examined. The hardness-intensity diagram shows a cyclical movement in the counterclockwise direction and possibly indicates the presence of two independent accretion flows: a thin-disk flow and a hot sub-Keplerian flow.
Published: 2001
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30. Superconducting electronics requirements for single-photon, energy resolving detectors

Author: Armen Gulian, D. Van Vechten, Gilbert G. Fritz, and Kent S. Wood
Subjects: Physics, Photon, Physics::Instrumentation and Detectors, business.industry, Preamplifier, Amplifier, Bolometer, Detector, Photon energy, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, law.invention, Optics, law, Optoelectronics, Electrical and Electronic Engineering, Image sensor, business, Energy (signal processing)
Abstract: Development of single photon sensors capable of determining the energy ("color") of each photon incident on a pixelated focal plane in real time is a central activity of many groups worldwide developing state-of-the-art hardware for the space astrophysics community. Terrestrial applications in materials analysis are also being targeted. The most successful class of approaches uses "hot-electron" microbolometers in which the energy of the photon elevates the electronic temperature in a metallic absorber and a dedicated thermometer measures this excursion. In a class of devices called thermoelectric microbolometers the temperature sensor utilizes the Seebeck effect. Estimates of theoretical performance for a complete megapixel array are quite positive and the prototype single-pixel devices are under test. Superconducting electronics is a critical part of the signal acquisition chain. Three different types of SQUID-array amplifiers coupled to our detector pixels have been tested. The parameters of optimized SQUID-array preamplifiers are discussed.
Published: 2001
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31. USA Experiment and [ITAL]RXTE[/ITAL] Observations of a Variable Low-Frequency Quasi-periodic Oscillation in XTE J1118+480

Author: G. Shabad, Kent S. Wood, Paul S. Ray, K. T. Reilly, Jeffrey D. Scargle, Gilbert G. Fritz, Daryl J. Yentis, P. M. Saz Parkinson, Michael P. Kowalski, Michael T. Wolff, G. Godfrey, R. M. Bandyopadhyay, Paul Hertz, B. Giebels, M. N. Lovellette, and Elliott D. Bloom
Subjects: Physics, Black hole, Quasi-periodic oscillation, Space and Planetary Science, Oscillation, Astrophysics::High Energy Astrophysical Phenomena, Flux, Astronomy, Astronomy and Astrophysics, Satellite, Astrophysics, Low frequency
Abstract: Using the USA Experiment on the Advanced Research and Global Observation Satellite and the Rossi X-Ray Timing Explorer, we have extensively observed the X-ray transient XTE J1118+480 during its recent outburst in 2000 April-June. We present detailed monitoring of the evolution of a low-frequency quasi-periodic oscillation (QPO) that drifts from 0.07 to 0.15 Hz during the outburst. We examine possible correlations of the QPO frequency with the flux and spectral characteristics of the source, and we compare this QPO with low-frequency QPOs observed in other black hole candidates.
Published: 2000
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32. X-ray/UV single photon detectors with isotropic Seebeck sensors

Author: Gilbert G. Fritz, T Jacobs, D. Van Vechten, Kent S. Wood, Armen Gulian, V. R. Nikogosyan, A.L. Gyulamiryan, and N. Giordano
Subjects: Physics, Nuclear and High Energy Physics, Photon, business.industry, Detector, Biasing, Microbolometer, Noise (electronics), Photon counting, Particle detector, Optics, Thermoelectric effect, Optoelectronics, business, Instrumentation
Abstract: A novel hot-electron microbolometer concept suitable for hyperspectral imaging at high photon counting rates is described. When each photon is absorbed, its energy is thermalized and homogenized within the normal-metal absorber to provide a highly reproducible temperature gradient across a thin film thermoelectric sensor which separates the absorber from a heat sink. The classical Seebeck effect results in an observable signal voltage, proportional to the time-dependent temperature gradient, without any externally applied bias current or voltage. Highly preliminary results on a single pixel device are presented and the projected performance of the fully developed device is analyzed, emphasizing the spectral resolution, noise sources, and suitability for large arrays of detector pixels.
Published: 2000
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33. Imaging detectors based on anisotropic thermoelectricity

Author: V. H. Vartanyan, Kent S. Wood, James S. Horwitz, D. Van Vechten, Gilbert G. Fritz, A.L. Gyulamiryan, Armen S. Kuzanyan, and Armen Gulian
Subjects: Physics, Nuclear and High Energy Physics, Photon, Condensed matter physics, Heat flux, Condensed Matter::Superconductivity, Detector, Thermoelectric effect, Tensor, Anisotropy, Instrumentation, Transient voltage suppressor, Particle detector
Abstract: Transient voltage pulses spontaneously occur in anisotropic films following the absorption of photons. Experiments on normal state YBCO unambiguously confirm that the pulses sensed between the sample ends arise from the thermoelectric response to the heat flux propagating through the film, perpendicular to the voltage measurement axis. Good agreement is found between the measured voltage characteristics and a macroscopic model based on the Seebeck tensor of the material. The applicability of such materials to single-photon detectors is discussed. A class of materials with sufficiently large low-temperature Seebeck tensor to construct a high resolution detector has been identified but not yet optimized for this use.
Published: 2000
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34. X‐Ray and Optical Observations of BL Hydri

Author: John Middleditch, Michael T. Wolff, Thomas Y. Steiman-Cameron, Kent S. Wood, and James N. Imamura
Subjects: Physics, AM Herculis, Astrophysics::High Energy Astrophysical Phenomena, Bremsstrahlung, Astronomy, White dwarf, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Light curve, Orbital period, Spectral line, Space and Planetary Science, Emission spectrum, Equivalent width, Astrophysics::Galaxy Astrophysics
Abstract: We acquired hard X-ray and unfiltered optical photometric data of the AM Herculis system BL Hydri. The X-ray data were obtained using the Proportional Counter Array detector of the Rossi X-Ray Timing Explorer satellite on 1997 October 17. The optical data were obtained using the 1.5 m telescope of the Cerro Tololo Inter-American Observatory on 1997 September 24. At the time of our observations, BL Hyi was in an unusual high-luminosity state with average visual magnitude mV ≈ 14.4 and orbital phase-averaged 2-10 keV X-ray flux ≈1.5 × 10-11 ergs cm-2 s-1, roughly 50% larger than had been seen previously. The X-ray light curves suggested that two accretion poles were active. The primary X-ray emission region was extended, covering ~45° in longitude on the white dwarf, while the secondary X-ray emission region was consistent with a point source with flux ~33% that of the primary region. The X-ray spectra were well fitted by absorbed bremsstrahlung with Gaussian emission-line models; and absorbed power law with Gaussian emission-line models. For the thermal models, the X-ray spectra were consistent with kTX ≈ 11 keV and an emission line at E ≈ 6.7-6.8 keV with equivalent width EW = 0.86-1.2 keV. The absorbed power-law models had slope α ≈ 2.1 and an emission line at E = 6.7-6.8 keV with EW = 1.1-1.5 keV. The optical data showed, 2.7% ± 0.2% rms quasi-periodic oscillations (QPOs) over the frequency range 0.2-0.8 Hz modulated strongly on the orbital period suggesting that the QPOs were connected with the dominant accretion hot spot. We did not find corresponding QPOs in the X-ray emission for an upper limit of 20% rms. There were no detections of other short-period QPOs or coherent features in either the optical or the X-ray data. The X-ray and optical data were consistent with a radiative shock model. Based primarily on the X-ray continuum and line spectrum, we infer that the mass of the white dwarf in the BL Hyi system is 0.3-0.7 M☉, depending on the relative cyclotron and hard X-ray luminosities.
Published: 1999
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35. Eclipse Timings of the Low‐Mass X‐Ray Binary EXO 0748−676. II. Detection of an Apparent Orbital Period Change and of Orbital Period Noise

Author: Kent S. Wood, L. R. Cominsky, and Paul Hertz
Subjects: Physics, Photon statistics, Astrophysics::High Energy Astrophysical Phenomena, Maximum likelihood, X-ray binary, Binary number, Astronomy, Astronomy and Astrophysics, Astrophysics, Orbital period, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Low Mass, Noise (radio), Eclipse
Abstract: The rare eclipsing low-mass X-ray binary EXO 0748-676 has now been monitored accurately for over a decade in the hope of detecting orbital period evolution. We report observations of 10 complete eclipses at resolution less than 0.1 s with the Rossi X-ray Timing Explorer during 1996 May and 1996 August. We have timed the eclipses with an accuracy limited by photon statistics to 0.2-0.5 s. When combined with historical measurements, the eclipse timings imply an unexpectedly large orbital period derivative, orb=3.3 × 10−11, and a rapid timescale for orbital evolution, τorb = 1.3 × 107 yr. The observations also require considerable intrinsic jitter in the mideclipse timings; a maximum likelihood estimate is 0.15 s per orbital cycle. We consider various models and scenarios that might account for these unexpected results.
Published: 1997
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36. Development of a new superconducting detector for the ultra-violet and soft X-ray regimes

Author: J. S. Horwitz, J.B. Thrasher, G.M. Daly, Mark G. Blamire, A.L. Gyulamiryan, R. B. Akopyan, Gilbert G. Fritz, V. H. Vartanyan, Kent S. Wood, D. Van Vechten, J. F. Pinto, Armen Gulian, and D. Koller
Subjects: Physics, X-ray astronomy, Pixel, business.industry, Resolution (electron density), Detector, Hyperspectral imaging, Large format, Condensed Matter Physics, Particle detector, Electronic, Optical and Magnetic Materials, Optics, Ultraviolet astronomy, Optoelectronics, Electrical and Electronic Engineering, business
Abstract: UV and X-ray astronomy need hyperspectral imaging devices, i.e. large format (1000/spl times/1000) arrays of pixels in which each single-photon event is tagged with spectral information. Such devices permit multicolor imagery and surveys to be obtained with a single camera. Here we discuss the first-stage of development of a new generation of UV/X-ray detectors that will provide 0.1-0.01% energy resolution in an array format.
Published: 1997
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37. Alternative non-equilibrium superconducting X-ray detectors

Author: Armen Gulian, Kent S. Wood, F. Scott Porter, and Deborah Van Vechten
Subjects: Physics, Josephson effect, Superconductivity, Nuclear and High Energy Physics, Operating temperature, Condensed matter physics, Condensed Matter::Superconductivity, Quasiparticle, Superconducting tunnel junction, Superconducting magnetic energy storage, Instrumentation, Particle detector, Quantum tunnelling
Abstract: Non-equilibrium X-ray detectors based on isotropic superconductor absorbers offer the hope of energy resolution limited by the statistics of excitation production, i.e., δEE ∼ (ΔE)12, where Δ is the superconducting gap energy. This can be numerically equal to that of the best bolometers at significantly higher operating temperatures. Superconducting Tunnel Junction Detectors (STJDs) count the X-ray event induced excitations (quasiparticles (QP)) as an excursion of the subgap tunnel current. While STJDs are presently the best studied QP readout scheme, they have made slow progress toward the limiting energy resolution. Some of the difficulties are enumerated herein and are inherent in tunnel junctions. One alternative is to measure the conductivity excursion of a superconducting film that follows photon absorption. This excursion obeys exactly the same equation as the effective quasiparticle tunneling conductivity in a Josephson junction. Hence the two schemes should produce the same readout waveforms when the same superconducting absorbers are used. Seven specific approaches to realizing the measurement are presented. All versions of the conductivity readout offer simpler sample fabrication than STJD. Any superconducting material may be used. In commercial applications, the obvious benefit in operating temperature of using the HTSC materials may more than compensate for the penalty in energy resolution.
Published: 1996
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38. Ruthenates: simple superconducting qubits

Author: Armen Gulian and Kent S. Wood
Subjects: Condensed Matter::Quantum Gases, Physics, Quantum decoherence, Energy Engineering and Power Technology, Quantum Physics, Quantum entanglement, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, law.invention, Computer Science::Emerging Technologies, law, Condensed Matter::Superconductivity, Qubit, Quantum mechanics, Electrical and Electronic Engineering, Triplet state, Cooper pair, Superconducting quantum computing, Entanglement distillation, Bose–Einstein condensate
Abstract: We propose triplet superconductors, such as ruthenates, as a prospective material for qubit construction. The vectorial nature of the order parameter in triplet superconductors makes it conceptually very easy to imagine the performance of the qubits. The Cooper condensate of pairs in triplet superconductors has all the attributes of the Bose–Einstein condensates and should facilitate long decoherence times of these qubits versus other “vectorial” schemes for qubits, such as small ferromagnets. There are other benefits, which the superconducting state provides for a requirement like entanglement between qubits via the proximity effect.
Published: 2004
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39. Determination of the Point-spread Function for the Fermi Large Area Telescope from On-orbit Data and Limits on Pair Halos of Active Galactic Nuclei

Author: G. Busetto, Brian L Winer, S. Cutini, A. A. Moiseev, Katsuaki Asano, Francesco Longo, Gudlaugur Johannesson, F. Loparco, E. Do Couto E Silva, W. Mitthumsiri, T. A. Porter, A. P. Waite, T. J. Brandt, Jean Ballet, Stefan Funk, Daniel Sánchez, Claudia Lavalley, Sho Nishino, Alex Drlica-Wagner, Justin Vandenbroucke, T. E. Stephens, A. Morselli, V. Vitale, Jeffrey D. Scargle, P. Fusco, Stefano Ciprini, Igor V. Moskalenko, Matthew Kerr, A. W. Borgland, I. A. Grenier, S. Germani, T. Ohsugi, Eleonora Troja, Miranda Jackson, Nicola Omodei, Guido Barbiellini, S. J. Fegan, Olaf Reimer, Zhenwei Yang, Elliott D. Bloom, G. Godfrey, Kent S. Wood, T. Jogler, Carmelo Sgrò, Riccardo Rando, Soebur Razzaque, Jay P. Norris, M. Razzano, P. Fortin, L. S. Rochester, C. Favuzzi, V. Vasileiou, R. Claus, Matthew Wood, Stephan Zimmer, J. F. Ormes, N. Gehrels, James Chiang, Hiroyasu Tajima, Gino Tosti, Jan Conrad, F. de Palma, R. E. Hughes, E. Wallace, Dario Gasparrini, Patrick Weltevrede, E. Nuss, Paola Grandi, P. Lubrano, Hiromitsu Takahashi, M. Brigida, Sylvain Chaty, A. Chekhtman, David Paneque, Claudia Cecchi, S. Rainò, J. G. Thayer, T. Kamae, Tsunefumi Mizuno, Randall P. Johnson, Rodrigo Nemmen, R. Dubois, E. Orlando, J. M. Casandjian, D. Horan, F. D'Ammando, W. B. Focke, M. Kuss, C. Monte, M. E. Monzani, Gloria Spandre, P. Spinelli, M. N. Mazziotta, Jun Kataoka, Pascal Bruel, J. Mehault, Emanuele Bonamente, R. Buehler, J. E. Grove, S. Larsson, T. L. Usher, Francesco Giordano, D. J. Thompson, Daniela Hadasch, M. Roth, Yasushi Fukazawa, T. H. Burnett, A. S. Johnson, M. Orienti, S. Murgia, O. Tibolla, Benoit Lott, Peter F. Michelson, Marcello Giroletti, Takaaki Tanaka, F. Piron, A. Snyder, Keith Bechtol, Johan Bregeon, Johann Cohen-Tanugi, Alice Allafort, Roberto Mignani, Eric Charles, Julie McEnery, Morihiro Hayashida, E. Hays, Steven Ritz, D. J. Suson, C. C. Cheung, W. McConville, L. C. Reyes, Marco Ajello, J. B. Thayer, M. Naumann-Godo, L. Tibaldo, W. B. Atwood, J. S. Perkins, Nicola Giglietto, F. Gargano, Luca Latronico, G. A. Caliandro, H. Poon, S. Colafrancesco, M. N. Lovellette, P. A. Caraveo, Persis S. Drell, M. Tinivella, Elizabeth C. Ferrara, V. Pelassa, E. J. Siskind, J. H. Panetta, Markus Ackermann, A. N. Cillis, R. A. Cameron, Luca Baldini, M. Pierbattista, Denis Bastieri, A. von Kienlin, C. Romoli, J. Lande, Sylvain Guiriec, A. Reimer, S. Buson, P. M. Saz Parkinson, Suk-Han Lee, Melissa Pesce-Rollins, T. Glanzman, Jürgen Knödlseder, G. Pivato, Eugenio Bottacini, Charles D. Dermer, X. Hou, Giacomo Vianello, Ronaldo Bellazzini, 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), Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Istituto Nazionale di Fisica Nucleare, sezione di Bari (INFN, sezione di Bari), Istituto Nazionale di Fisica Nucleare (INFN), GLAST, 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)-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 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), Ackermann, M., Ajello, M., Allafort, A., Asano, K., Atwood, W. B., Baldini, L., Ballet, J., BARBIELLINI AMIDEI, Guido, Bastieri, D., Bechtol, K., Bellazzini, R., Bloom, E. D., Bonamente, E., Borgland, A. W., Bottacini, E., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Burnett, T. H., Busetto, G., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Charles, E., Chaty, S., Chekhtman, A., Cheung, C. C., Chiang, J., Cillis, A. N., Ciprini, S., Claus, R., Cohen Tanugi, J., Colafrancesco, S., Conrad, J., Cutini, S., D'Ammando, F., de Palma, F., Dermer, C. D., Silva, E. do Couto e., Drell, P. S., Drlica Wagner, A., Dubois, R., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Fortin, P., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grandi, P., Grenier, I. A., Grove, J. E., Guiriec, S., Hadasch, D., Hayashida, M., Hays, E., Horan, D., Hou, X., Hughes, R. E., Jackson, M. S., Jogler, T., Jóhannesson, G., Johnson, R. P., Johnson, A. S., Kamae, T., Kataoka, J., Kerr, M., Knödlseder, J., Kuss, M., Lande, J., Larsson, S., Latronico, L., Lavalley, C., Lee, S. H., Longo, Francesco, Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Mazziotta, M. N., Mcconville, W., Mcenery, J. E., Mehault, J., Michelson, P. F., Mignani, R. P., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann Godo, M., Nemmen, R., Nishino, S., Norris, J. P., Nuss, E., Ohsugi, T., Omodei, N., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Pelassa, V., Perkins, J. S., Pesce Rollins, M., Pierbattista, M., Piron, F., Pivato, G., Poon, H., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Reyes, L. C., Ritz, S., Rochester, L. S., Romoli, C., Roth, M., Sanchez, D. A., Saz Parkinson, P. M., Scargle, J. D., Sgrò, C., Siskind, E. J., Snyder, A., Spandre, G., Spinelli, P., Stephens, T. E., Suson, D. J., Tajima, H., Takahashi, H., Tanaka, T., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tibaldo, L., Tibolla, O., Tinivella, M., Tosti, G., Troja, E., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., von Kienlin, A., Waite, A. P., Wallace, E., Weltevrede, P., Winer, B. L., Wood, K. S., Wood, M., Yang, Z., Zimmer, S., 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), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-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 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 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), Ackermann M, Ajello M, Allafort A, Asano K, Atwood WB, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Bloom ED, Bonamente E, Borgland AW, Bottacini E, Brandt TJ, Bregeon J, Brigida M, Bruel P, Buehler R, Burnett TH, Busetto G, Buson S, Caliandro GA, Cameron RA, Caraveo PA, Casandjian JM, Cecchi C, Charles E, Chaty S, Chekhtman A, Cheung CC, Chiang J, Cillis AN, Ciprini S, Claus R, Cohen-Tanugi J, Colafrancesco S, Conrad J, Cutini S, DAmmando F, de Palma F, Dermer CD, Silva EDE, Drell S, Drlica-Wagner A, Dubois R, Favuzzi C, Fegan SJ, Ferrara EC, Focke WB, Fortin P, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grandi P, Grenier IA, Grove JE, Guiriec S, Hadasch D, Hayashida M, Hays E, Horan D, Hou X, Hughes RE, Jackson MS, Jogler T, Johannesson G, Johnson RP, Johnson AS, Kamae T, Kataoka J, Kerr M, Knodlseder J, Kuss M, Lande J, Larsson S, Latronico L, Lavalley C, Lee SH, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Mazziotta MN, McConville W, McEnery JE, Mehault J, Michelson PF, Mignani RP, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Naumann-Godo M, Nemmen R, Nishino S, Norris JP, Nuss E, Ohsugi T, Omodei N, Orienti M, Orlando E, Ormes JF, Paneque D, Panetta JH, Pelassa V, Perkins JS, Pesce-Rollins M, Pierbattista M, Piron F, Pivato G, Poon H, Porter TA, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Reyes LC, Ritz S, Rochester LS, Romoli C, Roth M, Sanchez DA, Parkinson PMS, Scargle JD, Sgro C, Siskind EJ, Snyder A, Spandre G, Spinelli P, Stephens TE, Suson DJ, Tajima H, Takahashi H, Tanaka T, Thayer JG, Thayer JB, Thompson DJ, Tibaldo L, Tibolla O, Tinivella M, Tosti G, Troja E, Usher TL, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, von Kienlin A, Waite AP, Wallace E, Weltevrede P, Winer BL, Wood KS, Wood M, Yang Z, Zimmer S, National Institute for Nuclear Physics (INFN), and 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)
Subjects: Ciencias Físicas, EXTRAGALACTIC MAGNETIC-FIELDS, halo [galaxies], galaxies: halos, Astrophysics, 01 natural sciences, galaxies, [gamma rays], law.invention, Spitzer Space Telescope, law, 1ES 0229+200, SPACE-TELESCOPE, 010303 astronomy & astrophysics, Physics, TEV BLAZARS, detector [instrumentation], [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::Instrumentation and Methods for Astrophysics, detectors, intergalactic medium [instrumentation], VHE GAMMA-RAYS, galaxies: active – galaxies: halos – gamma rays: galaxies – instrumentation: detectors – intergalactic medium, halos [galaxies], active [galaxies], intergalactic medium, Astrophysics - High Energy Astrophysical Phenomena, CIENCIAS NATURALES Y EXACTAS, Point spread function, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Active galactic nucleus, Astrophysics::High Energy Astrophysical Phenomena, galaxies: active, Astrophysics::Cosmology and Extragalactic Astrophysics, Telescope, 0103 physical sciences, gamma rays: galaxies, instrumentation: detectors, galaxie [gamma rays], Blazar, SOURCE CATALOG, Astrophysics::Galaxy Astrophysics, BACKGROUND LIGHT, 010308 nuclear & particles physics, Astronomy, CONSTRAINTS, Astronomy and Astrophysics, Quasar, PULSAR, Galaxy, DISCOVERY, Astronomía, Space and Planetary Science, ddc:520, Fermi Gamma-ray Space Telescope
Abstract: The astrophysical journal 765(1), 54 (2013). doi:10.1088/0004-637X/765/1/54, The Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope is a pair-conversion telescope designed to detect photons with energies from ≈20 MeV to >300 GeV. The pre-launch response functions of the LAT were determined through extensive Monte Carlo simulations and beam tests. The point-spread function (PSF) characterizing the angular distribution of reconstructed photons as a function of energy and geometry in the detector is determined here from two years of on-orbit data by examining the distributions of γ rays from pulsars and active galactic nuclei (AGNs). Above 3 GeV, the PSF is found to be broader than the pre-launch PSF. We checked for dependence of the PSF on the class of γ-ray source and observation epoch and found none. We also investigated several possible spatial models for pair-halo emission around BL Lac AGNs. We found no evidence for a component with spatial extension larger than the PSF and set upper limits on the amplitude of halo emission in stacked images of low- and high-redshift BL Lac AGNs and the TeV blazars 1ES0229+200 and 1ES0347–121, Published by Univ.11032, Chicago, Ill. [u.a.]
Published: 2013
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40. Constraints on the Galactic Population of TeV Pulsar Wind Nebulae Using Fermi Large Area Telescope Observations

Author: Janet Conrad, A. Reimer, Xian Hou, M. Tinivella, A. S. Johnson, Elizabeth C. Ferrara, A. Morselli, R. Claus, Marianne Lemoine-Goumard, M. Brigida, Hiromitsu Takahashi, Frederic Piron, V. Vasileiou, Emanuele Bonamente, Kent S. Wood, S. Murgia, C. Cecchi, Dario Gasparrini, M. Orienti, T. Reposeur, Y. Takeuchi, Denis Bastieri, E. Do Couto E Silva, F. Giordano, T. A. Porter, J.H. Panetta, Alice K. Harding, Alex Drlica-Wagner, Melissa Pesce-Rollins, T. J. Brandt, R. C. G. Chaves, W. B. Focke, T. Jogler, John W. Hewitt, L. Falletti, Sylvain Guiriec, A. Chekhtman, E. D. Bloom, Akira Okumura, M. E. Monzani, J. S. Perkins, Nicola Giglietto, Jean Ballet, Markus Ackermann, Tsunefumi Mizuno, V. Vitale, Michael Mayer, Gudlaugur Johannesson, S. J. Fegan, M. N. Lovellette, Stefano Ciprini, J. B. Thayer, E. J. Siskind, Yoshiyuki Inoue, G. Chiaro, P. A. Caraveo, Persis S. Drell, Gino Tosti, Justin Vandenbroucke, R. E. Hughes, Guido Barbiellini, Takeshi Nakamori, T. Grégoire, Luca Baldini, G. Godfrey, Martino Marelli, F. Gargano, T. Ohsugi, J. E. Grove, Yasushi Fukazawa, Francesco Longo, T. Glanzman, Gloria Spandre, M.-H. Grondin, D. J. Thompson, Eleonora Troja, Miranda Jackson, Alice Allafort, M. N. Mazziotta, J. Chiang, F. de Palma, Morihiro Hayashida, J. G. Thayer, Yasunobu Uchiyama, M. Kuss, P. Fusco, Matthew Kerr, L. Di Venere, Giacomo Vianello, Jürgen Knödlseder, Y. Hanabata, Johann Cohen-Tanugi, G. Pivato, T. Kawano, R. Rousseau, C. Favuzzi, G. A. Caliandro, Eugenio Bottacini, Z. Yang, Eric Nuss, J. Lande, Charles D. Dermer, A. Franckowiak, A. B. Hill, Stefan Funk, Michael Werner, Eric Charles, E. Hays, Steven Ritz, D. J. Suson, Carmelo Sgrò, Riccardo Rando, Ronaldo Bellazzini, David Paneque, S. Rainò, Francesco Massaro, J. F. Ormes, S. Cutini, F. Loparco, W. Mitthumsiri, I. A. Grenier, David A. Smith, S. Buson, Fabio Acero, P. Lubrano, C. Monte, R. A. Cameron, Roger Blandford, L. Latronico, Rodrigo Nemmen, Kazuhiko Hayashi, Diego F. Torres, Elena Orlando, D. Horan, J. Mehault, Johan Bregeon, B. L. Winer, Julie McEnery, M. Roth, Marco Ajello, L. Tibaldo, D. Hadasch, Igor V. Moskalenko, Olaf Reimer, Pascal Bruel, Omar Tibolla, R. Buehler, A. Schulz, Peter F. Michelson, Marcello Giroletti, P. Spinelli, Keith Bechtol, Stefan Larsson, M. Razzano, P. M. Saz Parkinson, Filippo D'Ammando, T. Kamae, M. Dalton, 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), 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), 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), 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), Istituto Nazionale di Fisica Nucleare, sezione di Bari (INFN, sezione di Bari), Istituto Nazionale di Fisica Nucleare (INFN), FERMI, 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)-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), Acero F, Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Blandford RD, Bloom ED, Bonamente E, Bottacini E, Brandt TJ, Bregeon J, 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 Palma F, Dermer CD, Di Venere L, Silva EDE, Drell PS, Drlica-Wagner A, Falletti L, Favuzzi C, Fegan SJ, Ferrara EC, Focke WB, Franckowiak A, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Gregoire T, Grenier IA, Grondin MH, Grove JE, Guiriec S, Hadasch D, Hanabata Y, Harding AK, Hayashida M, Hayashi K, Hays E, Hewitt J, Hill AB, Horan D, Hou X, Hughes RE, Inoue Y, Jackson MS, Jogler T, Johannesson G, Johnson AS, Kamae T, Kawano T, Kerr M, Knodlseder J, Kuss M, Lande J, Larsson S, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lovellette MN, Lubrano P, Marelli M, Massaro F, Mayer M, Mazziotta MN, McEnery JE, Mehault J, Michelson PF, Mitthumsiri W, Mizuno T, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nakamori T, 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, Reimer A, Reimer O, Reposeur T, Ritz S, Roth M, Rousseau R, Parkinson PMS, Schulz A, Sgro C, Siskind EJ, Smith DA, Spandre G, Spinelli P, Suson DJ, Takahashi H, Takeuchi Y, Thayer JG, Thayer JB, Thompson DJ, Tibaldo L, Tibolla O, Tinivella M, Torres DF, Tosti G, Troja E, Uchiyama Y, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Werner M, Winer BL, Wood KS, Yang Z, 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)), 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 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), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-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 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), Acero, F., Ackermann, M., Ajello, M., Allafort, A., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Blandford, R. D., Bloom, E. D., Bonamente, E., Bottacini, E., Brandt, T. J., Bregeon, 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., D'Ammando, F., de Palma, F., Dermer, C. D., Di Venere, L., Silva, E. do Couto e., Drell, P. S., Drlica Wagner, A., Falletti, L., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grégoire, T., Grenier, I. A., Grondin, M. H., Grove, J. E., Guiriec, S., Hadasch, D., Hanabata, Y., Harding, A. K., Hayashida, M., Hayashi, K., Hays, E., Hewitt, J., Hill, A. B., Horan, D., Hou, X., Hughes, R. E., Inoue, Y., Jackson, M. S., Jogler, T., Jóhannesson, G., Johnson, A. S., Kamae, T., Kawano, T., Kerr, M., Knödlseder, J., Kuss, M., Lande, J., Larsson, S., Latronico, L., Lemoine Goumard, M., Longo, Francesco, Loparco, F., Lovellette, M. N., Lubrano, P., Marelli, M., Massaro, F., Mayer, M., Mazziotta, M. N., Mcenery, J. E., Mehault, J., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., 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., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Roth, M., Rousseau, R., Saz Parkinson, P. M., Schulz, A., Sgrò, C., Siskind, E. J., Smith, D. A., Spandre, G., Spinelli, P., Suson, D. J., Takahashi, H., Takeuchi, Y., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tibaldo, L., Tibolla, O., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Uchiyama, Y., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Werner, M., Winer, B. L., Wood, K. S., Yang, Z., 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), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), National Institute for Nuclear Physics (INFN), and 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)
Subjects: [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::High Energy Astrophysical Phenomena, Population, FOS: Physical sciences, Context (language use), Astrophysics, 01 natural sciences, law.invention, Telescope, Pulsar, law, 0103 physical sciences, Radiative transfer, Astrophysics::Solar and Stellar Astrophysics, education, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), education.field_of_study, 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::Instrumentation and Methods for Astrophysics, Spectral density, Astronomy and Astrophysics, gamma rays: general, Galactic plane, Space and Planetary Science, ddc:520, Physics::Accelerator Physics, Astrophysics - High Energy Astrophysical Phenomena, general [gamma rays], Fermi Gamma-ray Space Telescope
Abstract: Pulsar wind nebulae (PWNe) have been established as the most populous class of TeV gamma-ray emitters. Since launch, the Fermi Large Area Telescope (LAT)identified five high-energy (100MeV, Comment: 72 pages, 13 figures
Published: 2013
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41. THENuSTARX-RAY SPECTRUM OF HERCULES X-1: A RADIATION-DOMINATED RADIATIVE SHOCK

Author: Katja Pottschmidt, Fritz-Walter Schwarm, Michael T. Wolff, Amy M. Gottlieb, Felix Fürst, Diana M. Marcu-Cheatham, Kent S. Wood, Paul B. Hemphill, Peter A. Becker, and Jörn Wilms
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Opacity, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, Electromagnetic radiation, Accretion (astrophysics), Spectral line, Neutron star, Stars, Pulsar, Space and Planetary Science, 0103 physical sciences, Radiative transfer, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: We report new spectral modeling of the accreting X-ray pulsar Hercules X- 1. Our radiation-dominated radiative shock model is an implementation of the analytic work of Becker & Wolff on Comptonized accretion flows onto magnetic neutron stars. We obtain a good fit to the spin-phase averaged 4 to 78 keV X-ray spectrum observed by the Nuclear Spectroscopic Telescope Array during a main- on phase of the Her X-1 35-day accretion disk precession period. This model allows us to estimate the accretion rate, the Comptonizing temperature of the radiating plasma, the radius of the magnetic polar cap, and the average scattering opacity parameters in the accretion column. This is in contrast to previous phenomenological models that characterized the shape of the X-ray spectrum but could not determine the physical parameters of the accretion flow. We describe the spectral fitting details and discuss the interpretation of the accretion flow physical parameters., Accepted for publication in the Astrophysical Journal
Published: 2016
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42. Design considerations for STJ x-ray detectors

Author: Paul A. Warburton, E.C.G. Kirk, Gilbert G. Fritz, Robert A. Zacher, D. Van Vechten, Mark G. Blamire, Kent S. Wood, and Gregory G. Saulnier
Subjects: Physics, Superconductivity, Energy loss, Field (physics), business.industry, Detector, X-ray detector, Biasing, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Optics, Condensed Matter::Superconductivity, General Materials Science, business, Layer (electronics)
Abstract: The geometrical shape and layer thicknesses of superconducting tunnel junctions (STJ) influence their suitability as x-ray detectors. Examples relating to field biasing are discussed. Two related energy loss mechanisms are also modeled.
Published: 1993
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43. Escape of photoelectrons: a major energy resolution degrading mechanism in thin superconducting tunnel junction X-ray detectors

Author: D. Van Vechten and Kent S. Wood
Subjects: Physics, Photon, business.industry, X-ray detector, Photoelectric effect, Condensed Matter Physics, Particle detector, Electronic, Optical and Magnetic Materials, Tunnel effect, Optoelectronics, Superconducting tunnel junction, Quantum efficiency, Electrical and Electronic Engineering, Atomic physics, business, Quantum tunnelling
Abstract: The authors consider the consequences of fabricating integral X-ray detectors with thin electrodes, 0.17 mu m for Nb and 0.25 mu m for Sn, with 6-keV photons incident. A simple geometric argument demonstrates that energetic electron loss during the first 1 ps of each event will cause less than the full energy of the incident photon to be captured in a large fraction of the events. This reduces the ultimate energy resolution the devices can achieve. Use of thicker absorbers (electrodes) is thus highly desirable, both from this point of view and to increase the quantum efficiencies of the devices. Nb electrodes should be about 0.8- mu m thick to reduce the escape probability of photoelectrons of energy >or=5 eV during the first 1 ps of an event. >
Published: 1993
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44. Million Degree Plasmas in Extreme Ultraviolet (EUV) Astrophysics. White Paper in Response to Astro2010 Science Call

Author: Jeffrey L. Linsky, Michael P. Kowalski, Paula Szkody, J. M. Laming, Kent S. Wood, Tod E. Strohmayer, Edward M. Sion, Jay B. Holberg, Barry Y. Welsh, Michael J. Wolff, Martin A. Barstow, Andrea K. Dupree, Frederick C. Bruhweiler, Steve B. Howell, and Raymond G. Cruddace
Subjects: Physics, Active galactic nucleus, Astrophysics::High Energy Astrophysical Phenomena, White dwarf, Astronomy, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Accretion (astrophysics), Galaxy, Interstellar medium, Neutron star, Stars, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Stellar evolution, Astrophysics::Galaxy Astrophysics
Abstract: Million degree plasmas are ubiquitous in the Universe, and examples include the atmospheres of white dwarfs (WDs); accretion phenomena in young stars (classical T-Tauri), cataclysmic variables (CVs) and active galactic nuclei (AGN); the coronae of stars; and the interstellar medium (ISM) of our own galaxy and of others. Understanding their nature is fundamental to astrophysics. This White Paper addresses primarily two Astro2010 Thematic Science Areas, SSE and GAN, and has important implications for the other three areas.
Published: 2010
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45. Superconducting detectors for photon and particle spectroscopy: Criteria for transitions to normal state

Author: Deborah Van Vechten and Kent S. Wood
Subjects: Josephson effect, Physics, Superconductivity, Nuclear and High Energy Physics, Range (particle radiation), Photon, Measuring instrument, Gamma spectroscopy, Atomic physics, Instrumentation, Critical field, Particle detector
Abstract: The nonequilibrium state produced when a high energy (>1 keV) quanta interacts with a superconducting solid is the physical basis for many new detectors. The most common approaches magnetically monitor the phase of small “grains” (SGDs) or monitor transients in the quasiparticle tunneling current in voltage-biased Josephson junctions (TJDs). While the former requires transitions to the normal state for its signal, the latter's energy resolution is degraded by excursions in the order parameter. To facilitate detector design, this article quantifies how the choices of sample material, bath temperature and field bias combine to influence the magnitude and spatial extent of the thermal excursion. Extensive tables of materials parameters are included. A wide range of inherent effects including the magnetic field dependent latent heat of the transition are discussed in the context of the limitations they produce on the operating energy range and size of proposed SGD detectors. Superheated initial conditions are not considered because the need for automatic resetting in astrophysical X-ray spectroscopy. Of the 23 elemental superconductors, we show that as SGDs only 5 have maximum grain sizes larger than 10 μm and only 3 are usable for photons with energies above 100 keV. Alpha particle detectors will be restricted by conceptually equivalent physics. Only by using inhomogeneous initial states or local, rather than global, transitions may these restrictions on bolometric detectors be lessened.
Published: 1992
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46. Discovery Of Pulsations From The Pulsar J0205+6449 In Snr 3c 58 With The Fermi Gamma-Ray Space Telescope

Author: C. Monte, Seth Digel, M. Dormody, Jun Kataoka, W. N. Johnson, Denis Bastieri, Alessandro Brez, J. Lande, Sylvain Guiriec, P. M. Saz Parkinson, Randall P. Johnson, P. Fusco, Victoria M. Kaspi, Ö. Çelik, A. S. Johnson, Jürgen Knödlseder, D. J. Suson, A. Morselli, V. Vitale, M. Pepe, M. Brigida, F. Kuehn, Matthew Kerr, Y. Hanabata, P. L. Nolan, Brian L Winer, C. Meurer, J. Bregeon, C. Farnier, B. Giebels, I. A. Grenier, J. G. Thayer, M.-H. Grondin, Benjamin Stappers, A. A. Moiseev, A. Tramacere, A. P. Waite, Simon Johnston, Hiromitsu Takahashi, T. A. Porter, P. Wang, Gino Tosti, T. Glanzman, Richard N. Manchester, Takaaki Tanaka, T. L. Usher, R. E. Hughes, Emanuele Bonamente, G. Theureau, Margaret A. Livingstone, M. N. Mazziotta, A. A. Abdo, S. Germani, E. Hays, A. Y. Rodriguez, D. Parent, F. Loparco, Gloria Spandre, A. Bouvier, E. Orlando, G. Godfrey, Paulo C. C. Freire, T. Reposeur, Andrew Lyne, W. Mitthumsiri, D. Dumora, N. Kawai, A. W. Borgland, Hideaki Katagiri, Ismaël Cognard, P. Lubrano, T. Ylinen, D. J. Thompson, A. Reimer, Tyrel J. Johnson, James Chiang, Roger Blandford, A. Makeev, Johann Cohen-Tanugi, A. Van Etten, Igor V. Moskalenko, F. de Palma, A. De Angelis, Melissa Pesce-Rollins, R. Claus, M. S. Strickman, Olaf Reimer, M. Marelli, Nicola Omodei, M. Lemoine-Goumard, Claudia Cecchi, Michael Kramer, S. Murgia, B. Lott, M. E. Monzani, F. Piron, W. B. Atwood, Luca Baldini, M. Pierbattista, P. D. Smith, T. H. Burnett, S. Rainò, B. Berenji, Marco Ajello, J. B. Thayer, C. Favuzzi, J. M. Casandjian, Nicola Giglietto, Tsunefumi Mizuno, A. Chekhtman, M. Ziegler, K. Watters, Hartmut Sadrozinski, Gudlaugur Johannesson, E. Striani, Alice K. Harding, R. Dubois, L. Tibaldo, Charles D. Dermer, Felix Ryde, G. A. Caliandro, W. B. Focke, T. Ohsugi, M. N. Lovellette, S. Ritz, Hiroyasu Tajima, P. Spinelli, J. E. Grove, Guido Barbiellini, P. A. Caraveo, Persis S. Drell, Jan Conrad, Pascal Bruel, Y. Edmonds, Francesco Giordano, Yasushi Fukazawa, M. Frailis, L. S. Rochester, George Hobbs, C. C. Cheung, Keith Bechtol, Michael Keith, V. Vasileiou, Peter F. Michelson, Kent S. Wood, V. Pelassa, E. J. Siskind, Julie McEnery, Patrick Weltevrede, Neil Gehrels, Ronaldo Bellazzini, M. Razzano, J. H. Panetta, Diego F. Torres, Magnus Axelsson, N. Vilchez, David Sánchez, T. Kamae, Stephen E. Thorsett, Markus Ackermann, Luca Latronico, R. A. Cameron, Francesco Longo, Fernando Camilo, A. Sander, F. Gargano, Yasunobu Uchiyama, Roger W. Romani, E. Do Couto E Silva, Jean Ballet, Stefano Ciprini, Scott M. Ransom, Elliott D. Bloom, B. M. Baughman, Morihiro Hayashida, David S. Smith, Carmelo Sgrò, Riccardo Rando, E. Nuss, David Paneque, M. Kuss, Jonathan F. Ormes, Cristobal M. Espinoza, L. Guillemot, 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), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique et chimie de l'environnement (LPCE), Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Théorique et Astroparticules (LPTA), 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-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Fermi-LAT, Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), 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)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Abdo, A. A., Ackermann, M., Ajello, M., Atwood, W. B., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Baughman, B. M., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bouvier, A., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Caliandro, G. A., Cameron, R. A., Camilo, F., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Celik, O., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cognard, I., Cohen Tanugi, J., Conrad, J., Dermer, C. D., Angelis, A. d., Palma, F. d., Digel, S. W., Dormody, M., Silva, E. D. E., Drell, P. S., Dubois, R., Dumora, D., Edmonds, Y., Espinoza, C., Farnier, C., Favuzzi, C., Focke, W. B., Frailis, M., Freire, P. C. C., Fukazawa, Y., Fusco, P., Gargano, F., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Grondin, M. H., Grove, J. E., Guillemot, L., Guiriec, S., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Hobbs, G., Hughes, R. E., Johannesson, G., Johnson, A. S., Johnson, R. P., Johnson, T. J., Johnson, W. N., Johnston, S., Kamae, T., Kaspi, V. M., Katagiri, H., Kataoka, J., Kawai, N., Keith, M., Kerr, M., Knodlseder, J., Kramer, M., Kuehn, F., Kuss, M., Lande, J., Latronico, L., Lemoine Goumard, M., Livingstone, M., Longo, Francesco, Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Lyne, A. G., Makeev, A., Manchester, R. N., Marelli, M., Mazziotta, M. N., Mcenery, J. E., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nolan, P. L., Nuss, E., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Pesce Rollins, M., Pierbattista, M., Piron, F., Porter, T. A., Raino, S., Rando, R., Ransom, S. M., Razzano, M., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Rochester, L. S., Rodriguez, A. Y., Romani, R. W., Ryde, F., Sadrozinski, H. F. W., Sanchez, D., Sander, A., Parkinson, P. M. S., Sgro, C., Siskind, E. J., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Stappers, B. W., Striani, E., Strickman, M. S., Suson, D. J., Tajima, H., Takahashi, H., Tanaka, T., Thayer, J. B., Thayer, J. G., Theureau, G., Thompson, D. J., Thorsett, S. E., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Uchiyama, Y., Usher, T. L., Etten, A. V., Vasileiou, V., Vilchez, N., Vitale, V., Waite, A. P., Wang, P., Watters, K., Weltevrede, P., Winer, B. L., Wood, K. S., Ylinen, T., Ziegler, M., 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), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-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 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), and 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)
Subjects: [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Fermi satellite, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, High Energy Gamma-ray Astronomy, Luminosity, law.invention, Telescope, stars: neutron, Spitzer Space Telescope, Pulsar, law, pulsars: general, 0103 physical sciences, Supernova remnant, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Pulsars, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Green Bank Telescope, Astronomy, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Neutron star, [PHYS.ASTR.GA]Physics [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), High Energy Physics::Experiment, [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Astrophysics - High Energy Astrophysical Phenomena, Fermi Gamma-ray Space Telescope
Abstract: We report the discovery of gamma-ray pulsations (> 0.1 GeV) from the young radio and X-ray pulsar PSR J0205+6449 located in the Galactic supernova remnant 3C 58. Data in the gamma-ray band were acquired by the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope (formerly GLAST), while the radio rotational ephemeris used to fold gamma-rays was obtained using both the Green Bank Telescope and the Lovell telescope at Jodrell Bank. The light curve consists of two peaks separated by 0.49 +/- 0.01 +/- 0.01 cycles which are aligned with the X-ray peaks. The first gamma-ray peak trails the radio pulse by 0.08 +/- 0.01 +/- 0.01, while its amplitude decreases with increasing energy as for the other gamma-ray pulsars. Spectral analysis of the pulsed gamma-ray emission suggests a simple power law of index -2.1 +/- 0.1 +/- 0.2 with an exponential cut-off at 3.0 +1.1 -0.7 +/- 0.4 GeV. The first uncertainty is statistical and the second is systematic. The integral gamma-ray photon flux above 0.1 GeV is (13.7 +/- 1.4 +/- 3.0) x 10^(-8) /cm2/s, which implies for a distance of 3.2 kpc and assuming a broad fan-like beam a luminosity of 8.3 x 10^(34) ergs/s and an efficiency eta of 0.3%. Finally, we report a 95% upper limit on the flux of 1.7 x 10^(-8) /cm2/s for off-pulse emission from the object., 7 pages, 1 figure, accepted for publication in Astrophysical Journal Letters, contact author: Damien Parent
Published: 2009
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47. Probability of quasiparticle self-trapping due to localized energy deposition in nonequilbrium tunnel-junction detectors

Author: Kent S. Wood and Deborah Van Vechten
Subjects: Physics, Tunnel effect, Condensed matter physics, Tunnel junction, Cascade, Condensed Matter::Superconductivity, Energy cascade, Quasiparticle, Non-equilibrium thermodynamics, Superconducting tunnel junction, Quantum efficiency, Atomic physics, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect
Abstract: Voltage-biased, superconducting tunnel junctions are investigated as x-ray detectors for applications requiring both high quantum efficiency and better than 1% energy resolution. The nonequilibrium quasiparticles, produced as the energy deposited degrades to the few-meV-per-excitation level, tunnel and are detected before they are lost to recombination. Previous event modeling ignored the energy cascade under the assumption that the equilibrium of the electrodes is minimally perturbed by the deposited energy. In this paper we demonstrate that that assumption is invalid. We calculate the local energy density as the average quasiparticle energy becomes of the proper magnitude to suppress the gap. The fraction of the nonequilibrium quasiparticles that become spatially trapped (never to tunnel) in the order-parameter well that their existence creates may vary between events. If so, the source of the observed non-Poisson-limited energy resolution of this class of detectors would be identified. The input parameters used were evaluated in equilibrium. Thus our conclusions need to be confirmed via a fully nonequilibrium calculation of the cascade.
Published: 1991
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48. Modeling quasiparticle production and propagation in tunnel junction based X-ray detectors

Author: M. N. Lovellette, Kent S. Wood, and D. Van Vechten
Subjects: Josephson effect, Physics, Condensed matter physics, Phonon, Monte Carlo method, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Particle detector, Electronic, Optical and Magnetic Materials, Tunnel effect, Tunnel junction, Condensed Matter::Superconductivity, Quasiparticle, Electrical and Electronic Engineering, Quantum tunnelling
Abstract: Optimization of the energy resolution of Josephson tunnel junction X-ray detectors requires the minimization of event-to-event variation in the number of nonequilibrium quasiparticles that tunnel and are thereby detected for monochromatic input. This requires a detailed understanding of the determinants of the time scales for the degradation of the energy and expansion of the disturbed volume, of possible quasiparticle (QP) self-trapping and phonon bottlenecking, and of the impact of materials parameters such as grain size. Moreover, the signals of distributed detectors cannot be interpreted without a detailed model of the evolution of the spatial variation in QP density. These matters, and the extent to which the details of the QP tunneling pulse probes the energy degradation and expansion, are discussed. The expansion is modeled in two dimensions with Monte Carlo simulations of ballistic quasiparticle propagation between randomizing collisions and compared with published data for a distributed junction detector. Alternative explanations of the high quasiparticle loss rate and curvature seen in the published plots of the relative fraction of the QP detected by the two sensing junctions are offered.
Published: 1991
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49. X-ray transients and flares from active stellar systems

Author: Kent S. Wood and Carol Ambruster
Subjects: Physics, Stars, law, Sky, media_common.quotation_subject, Flare star, X-ray, Astrophysics, Survey experiment, Light curve, Flare, law.invention, media_common
Abstract: Many X-ray flares detected to date from active cool stars were initially discovered as fast (≲ 3 hour) transients1,2,3. A survey of the HEAO A-1 Sky Survey Experiment 0.5–20 keV data for fast transients confirms the tendency for a significant fraction of such events to be associated with active stellar systems. Eight months of the mission (which include one full scan of the sky) were searched, yielding 10 transients of which three are identified with flares on cool stars. Of the remaining sources4, all but ones5 are at least consistent in their X-ray properties with a stellar flare origin.
Published: 2008
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50. Improved Cosmological Constraints from New, Old and Combined Supernova Datasets

Author: Kowalski, M, Rubin, D, Aldering, G, Agostinho, RJ, Amadon, A, Amanullah, R, Balland, C, Barbary, K, Blanc, G, Challis, PJ, Conley, A, Connolly, NV, Covarrubias, R, Dawson, KS, Deustua, SE, Ellis, R, Fabbro, S, Fadeyev, V, Fan, X, Farris, B, Folatelli, G, Frye, BL, Garavini, G, Gates, EL, Germany, L, Goldhaber, G, Goldman, B, Goobar, A, Groom, DE, Haissinski, J, Hardin, D, Hook, I, Kent, S, Kim, AG, Knop, RA, Lidman, C, Linder, EV, Mendez, J, Meyers, J, Miller, GJ, Moniez, M, Mourao, AM, Newberg, H, Nobili, S, Nugent, PE, Pain, R, Perdereau, O, Perlmutter, S, Phillips, MM, Prasad, V, Quimby, R, Regnault, N, Rich, J, Rubenstein, EP, Ruiz-Lapuente, P, Santos, FD, Schaefer, BE, Schommer, RA, Smith, RC, Soderberg, AM, Spadafora, AL, Strolger, L-G, Strovink, M, Suntzeff, NB, Suzuki, N, Thomas, RC, Walton, NA, Wang, L, Wood-Vasey, WM, Yun, JL, Project, SC, 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 de Physique Nucléaire et de Hautes Énergies (LPNHE), 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), APC - Cosmologie, AstroParticule et Cosmologie (APC (UMR_7164)), 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)-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), California Institute of Technology (CALTECH), Department of Physics, Stockholm University, Laboratoire de l'Accélérateur Linéaire (LAL), 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), Supernova Cosmology Project, Fundação para a Ciência e a Tecnologia (Portugal), German Research Foundation, Department of Energy (US), 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), 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)-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), Université Paris-Sud - Paris 11 (UP11)-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)-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)-Physique Corpusculaire et Cosmologie - Collège de France (PCC), and Collège de France (CdF)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Collège de France (CdF)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], media_common.quotation_subject, Astrophysics::High Energy Astrophysical Phenomena, Cosmological parameters, Supernovae: general, FOS: Physical sciences, Astrophysics, Cosmological constant, Astrophysics::Cosmology and Extragalactic Astrophysics, Astronomy & Astrophysics, Type (model theory), Atomic, 01 natural sciences, 7. Clean energy, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Particle and Plasma Physics, astro-ph, 0103 physical sciences, Nuclear, cosmological parameters, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, media_common, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Equation of state (cosmology), Cosmology: observations, Astrophysics (astro-ph), Molecular, Astronomy and Astrophysics, observations [cosmology], Redshift, Universe, Supernova, Space and Planetary Science, Dark energy, High Energy Physics::Experiment, Supernova Legacy Survey, general [supernovae], Astronomical and Space Sciences, Physical Chemistry (incl. Structural)
Abstract: 30 pags., 17 figs., 12 tabs. 4 apps., We present a new compilation of Type Ia supernovae (SNe Ia), a new data set of low-redshift nearby-Hubble-flow SNe, and new analysis procedures to work with these heterogeneous compilations. This >Union> compilation of 414 SNe Ia, which reduces to 307 SNe after selection cuts, includes the recent large samples of SNe Ia from the Supernova Legacy Survey and ESSENCE Survey, the older data sets, as well as the recently extended data set of distant supernovae observed with the Hubble Space Telescope (HST). A single, consistent, and blind analysis procedure is used for all the various SN Ia subsamples, and a new procedure is implemented that consistently weights the heterogeneous data sets and rejects outliers. We present the latest results from this Union compilation and discuss the cosmological constraints from this new compilation and its combination with other cosmological measurements (CMB and BAO). The constraint we obtain from supernovae on the dark energy density is ¿¿ = 0.713+ 0.027¿0.029(stat)+ 0.036¿0.039(sys) , for a flat, ¿CDM universe. Assuming a constant equation of state parameter, w, the combined constraints from SNe, BAO, and CMB give w = ¿ 0.969+ 0.059¿0.063(stat)+ 0.063¿0.066(sys) . While our results are consistent with a cosmological constant, we obtain only relatively weak constraints on a w that varies with redshift. In particular, the current SN data do not yet significantly constrain w at z > 1. With the addition of our new nearby Hubble-flow SNe Ia, these resulting cosmological constraints are currently the tightest available., This work was supported in part by the Director, Office of Science, Office of High Energy and Nuclear Physics, US Department of Energy, through contract DE-AC02-05CH11231. This research used resources of the National Energy Research Scientific Computing Center, which is supported by the Office of Science of the US Department of Energy under contract DEAC02- 05CH11231. The use of Portuguese time for the YALO telescope was supported by Fundacao para a Ciencia e Tecnologia, Portugal, and by Project PESO/ESO/P/PRO/1257/98. M. K. acknowledges support from the Deutsche Forschungsgemeinschaft (DFG). P. E. N. acknowledges support from the USDepartment of Energy Scientific Discovery throughAdvanced Computing program under contract DE-FG02-06ER06-04. A.M. M. acknowledges financial support from Fundacao para a Ciencia e Tecnologia (FCT), Portugal, through project PESO/P/PRO/ 15139/99.
Published: 2008
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