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1. External Heat Storage and Energy Generation Pole: Experimental Investigation and Modelling of a Novel Sustainable Solution for Building Temperature Control

Author

Carrigan, Svenja, Spiegel, Jonas, Schröter, Birke, Kornadt, Oliver, di Prisco, Marco, Series Editor, Chen, Sheng-Hong, Series Editor, Vayas, Ioannis, Series Editor, Kumar Shukla, Sanjay, Series Editor, Sharma, Anuj, Series Editor, Kumar, Nagesh, Series Editor, Wang, Chien Ming, Series Editor, Cui, Zhen-Dong, Series Editor, Lu, Xinzheng, Series Editor, and Berardi, Umberto, editor

Published
2025
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6. Exploring the Galaxy at TeV energies: Latest results from the H.E.S.S. Galactic Plane Survey

Author

Gast, Henning, Brun, François, Carrigan, Svenja, Chaves, Ryan C. G., Deil, Christoph, Djannati-Ataï, Arache, Gallant, Yves, Marandon, Vincent, de Naurois, Mathieu, and Reyes, Raquel de los

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The High Energy Stereoscopic System (H.E.S.S.) is an array of four imaging atmospheric-Cherenkov telescopes located in Namibia and designed to detect extensive air showers initiated by gamma-rays in the very-high-energy domain. It is an ideal instrument for surveying the Galactic plane in search of new sources, thanks to its location in the Southern Hemisphere, its excellent sensitivity, and its large field-of-view. The efforts of the H.E.S.S. Galactic Plane Survey, the first comprehensive survey of the inner Galaxy at TeV energies, have contributed to the discovery of an unexpectedly large and diverse population of over 60 sources of VHE gamma rays within its current range of l=250 to 65 degrees in longitude and |b|<=3.5 degrees in latitude. The population of VHE gamma-ray emitters is dominated by the pulsar wind nebula and supernova remnant source classes, although nearly a third remain unidentified or confused. The sensitivity of H.E.S.S. to sources in the inner Galaxy has improved significantly over the past two years, from continued survey observations, dedicated follow-up observations of interesting source candidates, and from the development of advanced methods for discrimination of gamma-ray-induced showers from the dominant background of hadron-induced showers. The latest maps of the Galaxy at TeV energies will be presented, and a few remarkable new sources will be highlighted., Comment: 4 pages, 2 figures, appears in the Proceedings of the 32nd International Cosmic Ray Conference (ICRC 2011), Beijing, China, 11th to 18th August 2011

Published
2012
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7. Very-high-energy gamma radiation from supernova remnants as seen with H.E.S.S

Author

Bochow, Anne, Carrigan, Svenja, Gast, Henning, Marandon, Vincent, Renaud, Matthieu, and Hofmann, Werner

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Very-high-energy (VHE, E > 100 GeV) gamma radiation has already been detected from several supernova remnants (SNRs). These objects, which are well-studied in radio, optical and X-ray wavelengths, constitute one of the most intriguing source classes in VHE astronomy. H.E.S.S., an array of four imaging atmospheric Cherenkov telescopes in Namibia, has recorded an extensive dataset of VHE gamma-ray observations covering the central region of the Milky Way, both from pointed observations as well as from the Galactic Plane Survey conducted in the inner region of the Galaxy. From radio observations, several hundred SNRs are known in the Milky Way, but until now only few of them have been identified as VHE gamma-ray emitters. Using the H.E.S.S. dataset and a large ensemble of radio SNRs localized in the inner region of the Galaxy, the standard framework that links the origin of cosmic rays to the gamma-ray visibility of SNRs can now be tested. Here we present the ensemble of investigated SNRs and discuss constraints on the parameter space used within a theoretical model of hadronic VHE gamma-ray production., Comment: Proceeding of the 32nd ICRC, August 11-18 2011, Beijing, China

Published
2011
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8. Discovery of VHE gamma-ray emission from the W49 region with H.E.S.S

Author

Brun, Francois, de Naurois, Mathieu, Hofmann, Werner, Carrigan, Svenja, Djannati-Ataï, Arache, and Ohm, Stefan

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The W49 region hosts two bright radio sources: the star forming region W49A and the supernova remnant W49B. The 10^6 M_odot Giant Molecular Cloud W49A is one of the most luminous giant radio HII regions in our Galaxy and hosts several active, high-mass star formation sites. The mixed-morphology supernova remnant W49B has one of the highest surface brightness in radio of all the SNRs of this class in our Galaxy and is one of the brightest ejecta-dominated SNRs in X-rays. Infrared observations evidenced that W49B is interacting with molecular clouds and Fermi recently reported the detection of a coincident bright, high-energy gamma-ray source. Observations by the H.E.S.S. telescope array resulted in the significant detection of VHE gamma-ray emission from the W49 region, compatible with VHE emission from the SNR W49B. The results, the morphology and the origin of the VHE emission are presented in the multi-wavelength context and the implications on the origin of the signal are discussed., Comment: 6 pages, 3 figures. Proc. of the 25th TEXAS Symposium on Relativistic Astrophysics. To appear in Proceedings of Science

Published
2011

9. A Smart Pixel Camera for future Cherenkov Telescopes

Author

Hermann, German, Carrigan, Svenja, Glück, Bernhard, and Hauser, Dominik

Subjects
Astrophysics
Abstract

The Smart Pixel Camera is a new camera for imaging atmospheric Cherenkov telescopes, suited for a next generation of large multi-telescope ground based gamma-ray observatories. The design of the camera foresees all electronics needed to process the images to be located inside the camera body at the focal plane. The camera has a modular design and is scalable in the number of pixels. The camera electronics provides the performance needed for the next generation instruments, like short signal integration time, topological trigger and short trigger gate, and at the same time the design is optimized to minimize the cost per channel. In addition new features are implemented, like the measurement of the arrival time of light pulses in the pixels on the few hundred psec timescale. The buffered readout system of the camera allows to take images at sustained rates of O(10 kHz) with a dead-time of only about 0.8 % per kHz., Comment: 8 pages, 5 figures; to appear in the proceedings of "Towards a Network of Atmospheric Cherenkov Detectors VII", 2005, Palaiseau, France

Published
2005

13. Energiegewinn und Energieeinspeicherung des Prototyps eines neuartigen Wärmespeicher‐ und Energieerzeugungssystems.

Author

Schröter, Birke, Spiegel, Jonas, Carrigan, Svenja, Kornadt, Oliver, Friedrich, Thomas, Wißbach, Michael, Platzek, Dieter, and Büscher, Wolfgang

Subjects
HEAT storage, ENERGY consumption, SOLAR collectors, HEAT exchangers, RENEWABLE energy sources, ENERGY storage, POWER plants
Abstract

Copyright of Bauphysik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2023
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20. Weiterentwicklung der Energieeinsparverordnung: Ansätze zur Berücksichtigung der Herstellungs‐, Nutzungs‐ und Instandhaltungsphase von Gebäuden.

Author

Schöndube, Tim, Beecken, Christoph, Becker, Sabine, Carrigan, Svenja, and Kornadt, Oliver

Subjects
APARTMENT buildings, BUILDING maintenance, ENERGY development, HOUSE construction, PLANT maintenance
Abstract

Copyright of Bauphysik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2020
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27. Performance of Multipor WI as exterior insulation.

Author

Carrigan, Svenja, Hartner, Marco, Hofmann, Markus, Kornadt, Oliver, and Schoch, Torsten

Subjects
*SPECIFIC heat capacity, *THERMAL conductivity, *THERMAL insulation, *THERMAL expansion, *HEAT transfer, *BUILDING envelopes
Abstract

Multipor WI is a mineral‐based interior insulation system with excellent insulation properties. It is dimensionally stable, vapor permeable, and nonflammable. In this paper the investigation of the processability and functionality of Multipor WI WLF 042 as an exterior insulation system is reported. On the campus of Technische Universität Kaiserslautern, a building was constructed with a new exterior insulation system of Multipor WI WLF 042, of 14 cm thickness. This insulation, which has so far only been used in the building interior, has a heat conductivity of λ = 0.042 W/(mK) and a density of ρ = 90 kg/m3. Its thermal expansion coefficient is α = 10–5/K and its specific heat capacity is c = 0.85 kJ/(kgK). It has a lower density and compression strength than Multipor mineral insulation boards for exterior use do. Temperature sensors were implemented in different layers of the building envelope, both in undisturbed areas and at thermal bridges. The building will be monitored for several years. First heat transfer simulations of two thermal bridges of the building demonstrate the excellent insulation properties of WI WLF 042. The investigation of the processability and functionality of Multipor WI WLF 042 as an exterior insulation system is presented. First simulations show the excellent insulation properties of the insulation. The building will be monitored for several years to provide data about the processability and functionality of Multipor WI WLF 042 as an exterior insulation system. [ABSTRACT FROM AUTHOR]

Published
2019
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28. HESS reveals a lack of TeV emission from the supernova remnant Puppis A (Research Note)

Author

Abramowski, Attila, Aharonian, Felix A., Benkhali, Faical Ait, Akhperjanian, A. G., Angüner, Ekrem Oǧuzhan, Backes, Michael, Balenderan, Shangkari, Balzer, Arnim, Barnacka, Anna, Becherini, Yvonne, Tjus, J. Becker, Berge, David, Bernhard, Sabrina, Bernlöhr, K., Birsin, E., Biteau, Jonathan, Boettcher, Markus, Boisson, Catherine, Bolmont, J., Bordas, Pol, Bregeon, Johan, Brun, Francois, Brun, Pierre, Bryan, Mark, Bulik, Tomasz, Carrigan, Svenja, Casanova, Sabrina, Chadwick, Paula M., Chakraborty, N., Chalme-Calvet, R., Chaves, Ryan C. G., Chretien, M., Colafrancesco, Sergio, Cologna, Gabriele, Conrad, Jan, Couturier, C., Cui, Y., Davids, I. D., Degrange, B., Deil, C., deWilt, P., Djannati-Ataï, A., Domainko, W., Donath, A., Dubus, G., Dutson, K., Dyks, J., Dyrda, M., Edwards, T., Egberts, Kathrin, Eger, P., Espigat, P., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fernandez, D., Fiasson, A., Fontaine, G., Foerster, A., Füssling, Matthias, Gabici, S., Gajdus, M., Gallant, Y. A., Garrigoux, T., Giavitto, G., Giebels, B., Glicenstein, J. F., Gottschall, D., Grondin, M. -H., Grudzinska, M., Hadasch, D., Haeffner, S., Hahn, J., Harris, J., Heinzelmann, G., Henri, G., Hermann, G., Hervet, O., Hillert, A., Hinton, James Anthony, Hofmann, W., Hofverberg, P., Holler, Maraike, Horns, D., Ivascenko, A., Jacholkowska, A., Jahn, C., Jamrozy, M., Janiak, M., Jankowsky, F., Jung-Richardt, I., Kastendieck, M. A., Katarzynski, K., Katz, U., Kaufmann, S., Khelifi, B., Kieffer, M., Klepser, S., Klochkov, D., Kluzniak, W., Kolitzus, D., Komin, Nu., Kosack, K., Krakau, S., Krayzel, F., Krueger, P. P., Laffon, H., Lamanna, G., Lefaucheur, J., Lefranc, V., Lemiere, A., Lemoine-Goumard, M., Lenain, J. -P., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Marx, R., Maurin, G., Maxted, N., Mayer, Michael, McComb, T. J. L., Mehault, J., Meintjes, P. J., Menzler, U., Meyer, M., Mitchell, A. M. W., Moderski, R., Mohamed, M., Mora, K., Moulin, E., Murach, T., de Naurois, M., Niemiec, J., Nolan, S. J., Oakes, L., Odaka, H., Ohm, S., Opitz, B., Ostrowski, M., Oya, I., Panter, M., Parsons, R. D., Arribas, M. Paz, Pekeur, N. W., Pelletier, G., Petrucci, P. -O, Peyaud, B., Pita, S., Poon, H., Puehlhofer, G., Punch, M., Quirrenbach, A., Raab, S., Reichardt, I., Reimer, A., Reimer, O., Renaud, M., de los Reyes, R., Rieger, F., Romoli, C., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Sahakian, V., Salek, D., Sanchez, David M., Santangelo, A., Schlickeiser, R., Schuessler, F., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Sol, H., Spanier, F., Spengler, G., Spies, F., Stawarz, L., Steenkamp, R., Stegmann, Christian, Stinzing, F., Stycz, K., Sushch, Iurii, Tavernet, J. -P., Tavernier, T., Taylor, A. M., Terrier, R., Tluczykont, M., Trichard, C., Valerius, K., van Eldik, C., van Soelen, B., Vasileiadis, G., Veh, J., Venter, C., Viana, A., Vincent, P., Vink, J., Voelk, H. J., Volpe, F., Vorster, M., Vuillaume, T., Wagner, S. J., Wagner, P., Wagner, R. M., Ward, M., Weidinger, M., Weitzel, Q., White, R., Wierzcholska, A., Willmann, P., Woernlein, A., Wouters, D., Yang, R., Zabalza, V., Zaborov, D., Zacharias, M., Zdziarski, A. A., Zech, A., and Zechlin, H. -S.

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Institut für Physik und Astronomie
Abstract

Context. Puppis A is an interesting similar to 4 kyr-old supernova remnant (SNR) that shows strong evidence of interaction between the forward shock and a molecular cloud. It has been studied in detail from radio frequencies to high-energy (HE, 0.1-100 GeV) gamma-rays. An analysis of the Fermi-LAT data has shown extended HE gamma-ray emission with a 0.2-100 GeV spectrum exhibiting no significant deviation from a power law, unlike most of the GeV-emitting SNRs known to be interacting with molecular clouds. This makes it a promising target for imaging atmospheric Cherenkov telescopes (IACTs) to probe the gamma-ray emission above 100 GeV. Aims. Very-high-energy (VHE, E >= 0.1 TeV) gamma-ray emission from Puppis A has been, for the first time, searched for with the High Energy Stereoscopic System (HESS.). Methods. Stereoscopic imaging of Cherenkov radiation from extensive air showers is used to reconstruct the direction and energy of the incident gamma-rays in order to produce sky images and source spectra. The profile likelihood method is applied to find constraints on the existence of a potential break or cutoff in the photon spectrum. Results. The analysis of the HESS. data does not reveal any significant emission towards Puppis A. The derived upper limits on the differential photon flux imply that its broadband gamma-ray spectrum must exhibit a spectral break or cutoff. By combining Fermi-LAT and HESS. measurements, the 99% confidence-level upper limits on such a cutoff are found to be 450 and 280 GeV, assuming a power law with a simple exponential and a sub-exponential cutoff, respectively. It is concluded that none of the standard limitations (age, size, radiative losses) on the particle acceleration mechanism, assumed to be continuing at present, can explain the lack of VHE signal. The scenario in which particle acceleration has ceased some time ago is considered as an alternative explanation. The HE/VHE spectrum of Puppis A could then exhibit a break of non-radiative origin (as observed in several other interacting SNRs, albeit at somewhat higher energies), owing to the interaction with dense and neutral material, in particular towards the NE region.

Published
2015

29. The H.E.S.S. Galactic plane survey

Author

Deil, Christoph, primary, Brun, Francois, additional, Carrigan, Svenja, additional, Chaves, Ryan, additional, Donath, Axel, additional, GAST, Henning, additional, Marandon, Vincent, additional, and Terrier, Regis, additional

Published
2016
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30. The H.E.S.S. Galactic plane survey poster

Author

Donath, Axel, primary, Brun, Francois, additional, Carrigan, Svenja, additional, Chaves, Ryan, additional, Deil, Christoph, additional, GAST, Henning, additional, Marandon, Vincent, additional, and Terrier, Regis, additional

Published
2016
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32. Search for extended gamma-ray emission around AGN with HESS and Fermi-LAT

Author

Abramowski, Attila, Aharonian, Felix A., Benkhali, Faical Ait, Akhperjanian, A. G., Angüner, Ekrem Oǧuzhan, Anton, Gisela, Backes, Michael, Balenderan, Shangkari, Balzer, Arnim, Barnacka, Anna, Becherini, Yvonne, Tjus, J. Becker, Bernlöhr, K., Birsin, E., Bissaldi, E., Biteau, Jonathan, Boettcher, Markus, Boisson, Catherine, Bolmont, J., Bordas, Pol, Brucker, J., Brun, Francois, Brun, Pierre, Bulik, Tomasz, Carrigan, Svenja, Casanova, Sabrina, Chadwick, Paula M., Chalme-Calvet, R., Chaves, Ryan C. G., Cheesebrough, A., Chretien, M., Colafrancesco, Sergio, Cologna, Gabriele, Conrad, Jan, Couturier, C., Cui, Y., Djannati-Ataï, A., Domainko, W., Dubus, G., Dutson, K., Dyks, J., Dyrda, M., Edwards, T., Egberts, Kathrin, Eger, P., Espigat, P., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fernandez, D., Fiasson, A., Fontaine, G., Foerster, A., Fussling, Matthias, Gajdus, M., Gallant, Y. A., Garrigoux, T., Giavitto, G., Giebels, B., Glicenstein, J. F., Grondin, M. -H., Grudzinska, M., Haeffner, S., Hahn, J., Harris, J., Heinzelmann, G., Henri, G., Hermann, G., Hervet, O., Hillert, A., Hinton, James Anthony, Hofmann, W., Hofverberg, P., Holler, M., Horns, D., Jacholkowska, A., Jahn, C., Jamrozy, M., Janiak, M., Jankowsky, F., Jung, I., Kastendieck, M. A., Katarzynski, K., Katz, U., Kaufmann, S., Khelifi, B., Kieffer, M., Klepser, S., Klochkov, D., Kluzniak, W., Kneiske, T., Kolitzus, D., Komin, Nu., Kosack, K., Krakau, S., Krayzel, F., Krueger, P. P., Laffon, H., Lamanna, G., Lefaucheur, J., Lemiere, A., Lemoine-Goumard, M., Lenain, J. -P., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Marx, R., Maurin, G., Maxted, N., Mayer, M., McComb, T. J. L., Mehault, J., Meintjes, P. J., Menzler, U., Meyer, M., Moderski, R., Mohamed, M., Moulin, E., Murach, T., Naumann, C. L., de Naurois, M., Niemiec, J., Nolan, S. J., Oakes, L., Odaka, H., Ohm, S., Wilhelmi, E. de Ona, Opitz, B., Ostrowski, M., Oya, I., Panter, M., Parsons, R. D., Arribas, M. Paz, Pekeur, N. W., Pelletier, G., Perez, J., Petrucci, P. -O., Peyaud, B., Pita, S., Poon, H., Puehlhofer, G., Punch, M., Quirrenbach, A., Raab, S., Raue, M., Reichardt, I., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Rob, L., Romoli, C., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Sahakian, V., Sanchez, David M., Santangelo, A., Schlickeiser, R., Schuessler, F., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Sol, H., Spengler, G., Spies, F., Stawarz, L., Steenkamp, R., Stegmann, Christian, Stinzing, F., Stycz, K., Sushch, Iurii, Tavernet, J. -P., Tavernier, T., Taylor, A. M., Terrier, R., Tluczykont, M., Trichard, C., Valerius, K., van Eldik, C., van Soelen, B., Vasileiadis, G., Venter, C., Viana, A., Vincent, P., Voelk, H. J., Volpe, F., Vorster, M., Vuillaume, T., Wagner, S. J., Wagner, P., Wagner, R. M., Ward, M., Weidinger, M., Weitzel, Q., White, R., Wierzcholska, A., Willmann, P., Woernlein, A., Wouters, D., Yang, R., Zabalza, V., Zacharias, M., Zdziarski, A. A., Zech, A., Zechlin, H. -S., and Malyshev, D.

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Institut für Physik und Astronomie, Astrophysics::Cosmology and Extragalactic Astrophysics
Abstract

Context. Very-high-energy (VHE; E > 100 GeV) gamma-ray emission from blazars inevitably gives rise to electron-positron pair production through the interaction of these gamma-rays with the extragalactic background light (EBL). Depending on the magnetic fields in the proximity of the source, the cascade initiated from pair production can result in either an isotropic halo around an initially- beamed source or a magnetically- broadened cascade :aux. Aims. Both extended pair-halo (PH) and magnetically broadened cascade (MBC) emission from regions surrounding the blazars 1ES 1101-232, IRS 0229+200, and PKS 2155-304 were searched for using VHE y-ray data taken with the High Energy Stereoscopic System (HESS.) and high-energy (HE; 100 MeV < E < 100 GeV) gamma-ray data with the Fermi Large Area Telescope (LAT). Methods. By comparing the angular distributions of the reconstructed gamma-ray events to the angular profiles calculated from detailed theoretical models, the presence of PH and MBC was investigated. Results. Upper limits on the extended emission around lES 1101-232, lES 0229+200, and PKS 2155-304 are found to be at a level of a few per cent of the Crab nebula flux above 1 TeV, depending on the assumed photon index of the cascade emission. Assuming strong extra-Galactic magnetic field (EGME) values, >10(-12) G, this limits the production of pair haloes developing from electromagnetic cascades. For weaker magnetic fields, in which electromagnetic cascades would result in MBCs. EGMF strengths in the range (0.3-3) x 10(-15) G were excluded for PKS 2155-304 at the 99% confidence level, under the assumption of a 1 Mpc coherence length.

Published
2014

33. Autoclaved aerated concrete: Influence of heat storage capacity on thermal performance and thermal comfort.

Author

Schöndube, Tim, Rashid, Saif, Carrigan, Svenja, Schoch, Torsten, and Kornadt, Oliver

Subjects
HEAT storage, LIGHTWEIGHT construction, ATMOSPHERIC temperature
Abstract

Copyright of Mauerwerk is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2018
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34. Discovery of very high energy γ -ray emission from the BL Lacertae object PKS 0301−243 with H.E.S.S

Author

Abramowski, Attila, Acero, F., Aharonian, Felix A., Benkhali, Faical Ait, Akhperjanian, A. G., Angüner, Ekrem Oǧuzhan, Anton, Gisela, Balenderan, Shangkari, Balzer, Arnim, Barnacka, Anna, Becherini, Yvonne, Tjus, J. Becker, Bernlöhr, K., Birsin, E., Bissaldi, E., Biteau, Jonathan, Boettcher, Markus, Boisson, Catherine, Bolmont, J., Bordas, Pol, Brucker, J., Brun, Francois, Brun, Pierre, Bulik, Tomasz, Carrigan, Svenja, Casanova, Sabrina, Cerruti, M., Chadwick, Paula M., Chalme-Calvet, R., Chaves, Ryan C. G., Cheesebrough, A., Chretien, M., Colafrancesco, Sergio, Cologna, Gabriele, Conrad, Jan, Couturier, C., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., deWilt, P., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O&rsquo, Dubus, G., Dutson, K., Dyks, J., Dyrda, M., Edwards, T., Egberts, Kathrin, Eger, P., Espigat, P., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fernandez, D., Fiasson, A., Fontaine, G., Foerster, A., Fuessling, M., Gajdus, M., Gallant, Y. A., Garrigoux, T., Giebels, B., Glicenstein, J. F., Grondin, M. -H., Grudzinska, M., Haeffner, S., Hague, J. D., Hahn, J., Harris, J., Heinzelmann, G., Henri, G., Hermann, G., Hervet, O., Hillert, A., Hinton, James Anthony, Hofmann, W., Hofverberg, P., Holler, M., Horns, D., Jacholkowska, A., Jahn, C., Jamrozy, M., Janiak, M., Jankowsky, F., Jung, I., Kastendieck, M. A., Katarzynski, K., Katz, U., Kaufmann, S., Khelifi, B., Kieffer, M., Klepser, S., Klochkov, D., Kluzniak, W., Kneiske, T., Kolitzus, D., Komin, Nu., Kosack, K., Krakau, S., Krayzel, F., Krueger, P. P., Laffon, H., Lamanna, G., Lefaucheur, J., Lemoine-Goumard, M., Lenain, J. -P., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Marx, R., Maurin, G., Maxted, N., Mayer, M., McComb, T. J. L., Medina, M. C., Mehault, J., Menzler, U., Meyer, M., Moderski, R., Mohamed, M., Moulin, E., Murach, T., Naumann, C. L., de Naurois, M., Nedbal, D., Niemiec, J., Nolan, S. J., Oakes, L., Ohm, S., Wilhelmi, E. de Ona, Opitz, B., Ostrowski, M., Oya, I., Panter, M., Parsons, R. D., Arribas, M. Paz, Pekeur, N. W., Pelletier, G., Perez, J., Petrucci, P. -O., Peyaud, B., Pita, S., Poon, H., Puehlhofer, G., Punch, M., Quirrenbach, A., Raab, S., Raue, M., Reimer, A., Reimer, O., Renaud, M., de los Reyes, R., Rieger, F., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Sahakian, V., Sanchez, David M., Santangelo, A., Schlickeiser, R., Schuessler, F., Schulz, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Sol, H., Spengler, G., Spies, F., Stawarz, L., Steenkamp, R., Stegmann, Christian, Stinzing, F., Stycz, K., Sushch, Iurii, Szostek, A., Tavernet, J. -P., Terrier, R., Tluczykont, M., Trichard, C., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Viana, A., Vincent, P., Voelk, H. J., Volpe, F., Vorster, M., Wagner, S. J., Wagner, P., Ward, M., Weidinger, M., Weitzel, Q., White, R., Wierzcholska, A., Willmann, P., Woernlein, A., Wouters, D., Zacharias, M., Zajczyk, A., Zdziarski, A. A., Zech, A., Zechlin, H. -S., 12006653 - Venter, Christo, 11005394 - Krüger, Petrus Paulus, 22050574 - Pekeur, Nicolette Whilna, 24420530 - Böttcher, Markus, 23909196 - Casanova, Sabrina, 24922986 - Sushch, Iurii, 12792322 - Vorster, Michael Johannes, A., Abramowski, F., Acero, F., Aharonian, F. A., Benkhali, A. G., Akhperjanian, E., Anguener, G., Anton, S., Balenderan, A., Balzer, A., Barnacka, Y., Becherini, J. B., Tju, K., Bernloehr, E., Birsin, Bissaldi, Elisabetta, J., Biteau, M., Boettcher, C., Boisson, J., Bolmont, P., Borda, J., Brucker, F., Brun, P., Brun, T., Bulik, S., Carrigan, S., Casanova, M., Cerruti, P. M., Chadwick, R., Chalme Calvet, R. C., G., A., Cheesebrough, M., Chretien, S., Colafrancesco, G., Cologna, J., Conrad, C., Couturier, M., Dalton, M. K., Daniel, I. D., David, B., Degrange, C., Deil, P., Dewilt, H. J., Dickinson, A., Djannati Atai, W., Domainko, L. O., '., G., Dubu, K., Dutson, J., Dyk, M., Dyrda, T., Edward, K., Egbert, P., Eger, P., Espigat, C., Farnier, S., Fegan, F., Feinstein, M. V., Fernande, D., Fernandez, A., Fiasson, G., Fontaine, A., Foerster, M., Fuessling, M., Gajdu, Y. A., Gallant, T., Garrigoux, B., Giebel, J. F., Glicenstein, M. . ., H., M., Grudzinska, S., Haeffner, J. D., Hague, J., Hahn, J., Harri, G., Heinzelmann, G., Henri, G., Hermann, O., Hervet, A., Hillert, J. A., Hinton, W., Hofmann, P., Hofverberg, M., Holler, D., Horn, A., Jacholkowska, C., Jahn, M., Jamrozy, M., Janiak, F., Jankowsky, I., Jung, M. A., Kastendieck, K., Katarzynski, U., Katz, S., Kaufmann, B., Khelifi, M., Kieffer, S., Klepser, D., Klochkov, W., Kluzniak, T., Kneiske, D., Kolitzu, N., Komin, K., Kosack, S., Krakau, F., Krayzel, P. P., Krueger, H., Laffon, G., Lamanna, J., Lefaucheur, M., Lemoine Goumard, J. . ., P., D., Lennarz, T., Lohse, A., Lopatin, C. . ., C., V., Marandon, A., Marcowith, R., Marx, G., Maurin, N., Maxted, M., Mayer, T. J., L., M. C., Medina, J., Mehault, U., Menzler, M., Meyer, R., Moderski, M., Mohamed, E., Moulin, T., Murach, C. L., Naumann, M. d., Nauroi, D., Nedbal, J., Niemiec, S. J., Nolan, L., Oake, S., Ohm, E. d., Ona, B., Opitz, M., Ostrowski, I., Oya, M., Panter, R. D., Parson, M. P., Arriba, N. W., Pekeur, G., Pelletier, J., Perez, P. . ., O., B., Peyaud, S., Pita, H., Poon, G., Puehlhofer, M., Punch, A., Quirrenbach, S., Raab, M., Raue, A., Reimer, O., Reimer, M., Renaud, R. d., Lo, F., Rieger, L., Rob, S., Rosier Lee, G., Rowell, B., Rudak, C. B., Rulten, V., Sahakian, D. A., Sanchez, A., Santangelo, R., Schlickeiser, F., Schuessler, A., Schulz, U., Schwanke, S., Schwarzburg, S., Schwemmer, H., Sol, G., Spengler, F., Spie, L., Stawarz, R., Steenkamp, C., Stegmann, F., Stinzing, K., Stycz, I., Sushch, A., Szostek, R., Terrier, M., Tluczykont, C., Trichard, K., Valeriu, C. v., Eldik, G., Vasileiadi, C., Venter, A., Viana, P., Vincent, H. J., Voelk, F., Volpe, M., Vorster, S. J., Wagner, P., Wagner, M., Ward, M., Weidinger, Q., Weitzel, R., White, A., Wierzcholska, P., Willmann, A., Woernlein, D., Wouter, M., Zacharia, A., Zajczyk, A. A., Zdziarski, A., Zech, H. . ., S., AstroParticule et Cosmologie (APC (UMR_7164)), 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 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), 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), H.E.S.S. Collaboration, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, 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), 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), and 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)

Subjects
Active galactic nucleus, active [Galaxies], Opacity, Ciencias Físicas, Astrophysics::High Energy Astrophysical Phenomena, galaxies: active, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 7. Clean energy, 01 natural sciences, non-thermal. [Radiation mechanisms], purl.org/becyt/ford/1 [https], Gamma ray galaxies, BL Lacertae objects: individual: PKS 0301-243, gamma rays: galaxies, 0103 physical sciences, Radiation mechanisms, galaxie [gamma rays], individual: PKS 0301-243 [BL Lacertae objects], High Energy Stereoscopic System, 010303 astronomy & astrophysics, BL Lacertae objects: general, Galaxies: active, Gamma rays: galaxies, Radiation mechanisms: non-thermal, PKS 0301-243 (objeto BL Lacertae), Non thermal mechanisms, Physics, general [BL Lacertae objects], 010308 nuclear & particles physics, Gamma ray, Astronomy and Astrophysics, purl.org/becyt/ford/1.3 [https], radiation mechanisms: non-thermal, non-thermal [radiation mechanisms], Light curve, Redshift, Astronomía, Extragalactic background light, 13. Climate action, Space and Planetary Science, galaxies [gamma rays], Active galaxies, BL Lacertae objects, ddc:520, High Energy Physics::Experiment, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], CIENCIAS NATURALES Y EXACTAS, BL Lac object
Abstract

The active galactic nucleus PKS 0301−243 (z = 0.266) is a high-synchrotron-peaked BL Lac object that is detected at high energies (HE, 100 MeV 100 GeV) by the High Energy Stereoscopic System (H.E.S.S.) from observations between September 2009 and December 2011 for a total live time of 34.9 h. Gamma rays above 200 GeV are detected at a significance of 9.4σ. A hint of variability at the 2.5σ level is found. An integral flux I(E > 200 GeV) = (3.3 ± 1.1stat ± 0.7syst) × 10-12 ph cm-2 s-1 and a photon index Γ = 4.6 ± 0.7stat ± 0.2syst are measured. Multi-wavelength light curves in HE, X-ray and optical bands show strong variability, and a minimal variability timescale of eight days is estimated from the optical light curve. A single-zone leptonic synchrotron self-Compton scenario satisfactorily reproduces the multi-wavelength data. In this model, the emitting region is out of equipartition and the jet is particle dominated. Because of its high redshift compared to other sources observed at TeV energies, the very high energy emission from PKS 0301−243 is attenuated by the extragalactic background light (EBL) and the measured spectrum is used to derive an upper limit on the opacity of the EBL. Fil: Abramowski, A.. Universitat Hamburg; Alemania Fil: Acero, F.. Universite Montpellier II; Francia Fil: Aharonian, F.. Max Planck Institut für Kernphysik; Alemania Fil: Benkhali, F. Ait. Max Planck Institut für Kernphysik; Alemania Fil: Akhperjanian, A. G.. National Academy of Sciences of the Republic of Armenia; Armenia Fil: Medina, Maria Clementina. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomia; Argentina Fil: Valerius, K.. Universität Erlangen Nürnberg; Alemania Fil: van Eldik, C.. Universität Erlangen Nürnberg; Alemania Fil: Vasileiadis, G.. Universite Montpellier II; Francia Fil: Venter, C.. North West University; Sudáfrica Fil: Viana, A.. Max Planck Institut für Kernphysik; Alemania Fil: Vincent, P.. Université Paris Diderot - Paris 7; Francia Fil: Völk, H. J.. Max Planck Institut für Kernphysik; Alemania Fil: Volpe, F.. Max Planck Institut für Kernphysik; Alemania Fil: Vorster, M.. North West University; Sudáfrica Fil: Wagner, S. J.. Universität Heidelberg; Alemania Fil: Wagner, P.. Humboldt Universität zu Berlin; Alemania Fil: Ward, M.. University Of Durham; Reino Unido Fil: Weidinger, M.. Ruhr-universität Bochum; Alemania Fil: Weitzel, Q.. Max Planck Institut für Kernphysik; Alemania Fil: White, R.. The University of Leicester; Reino Unido Fil: Wierzcholska, A.. Uniwersytet Jagiellonski; Polonia Fil: Willmann, P.. Universität Erlangen Nürnberg; Alemania Fil: Wörnlein, A.. Universität Erlangen Nürnberg; Alemania Fil: Wouters, D.. CEA Saclay; Francia Fil: Zacharias, M.. Ruhr-universität Bochum; Alemania Fil: Zajczyk, A.. Universite Montpellier II; Francia Fil: Zdziarski, A. A.. Nicolaus Copernicus Astronomical Center; Polonia Fil: Zech, A.. Université Paris Diderot - Paris 7; Francia Fil: Zechlin, H. S.. Universitat Hamburg; Alemania

Published
2013
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35. Pulsar Wind Nebulae with H.E.S.S.: Establishing a Connection between high-power Pulsars and very-high-energy gamma-ray Sources

Author

Carrigan, Svenja

Subjects
530 Physics, Astrophysics::High Energy Astrophysical Phenomena
Abstract

Pulsars energise particles into lighthouse pencil beams and create extended relativistic outflows, pulsar wind nebulae (PWNe). In the very-high-energy (VHE) gamma-ray wave band, these PWNe represent to date the most populous class of Galactic sources. Nevertheless, the details of the energy conversion mechanisms in the vicinity of pulsars are not well understood, nor is it known which pulsars are able to drive PWNe and emit high-energy radiation. Due to its large field of view and unprecedented sensitivity, H.E.S.S. is the first instrument to allow for deep surveys of the Galactic plane in VHE gamma rays. This work presents the first ever systematic investigation of the connection of VHE gamma-ray sources and PWNe. Besides presenting two new candidate PWNe detected in this search, it is shown that pulsars with large spin-down energy flux are indeed with high probability associated with VHE gamma-ray sources, implying the existence of an efficient mechanism by which a large fraction of pulsar spin-down energy is converted into kinetic energy of particles. The results presented here make it very likely that future more sensitive VHE gamma-ray instruments will detect a rapidly increasing number of lower-luminosity PWNe.

Published
2007
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36. A population of gamma-ray emitting globular clusters seen with the Fermi Large Area Telescope

Author

Abdo, Aous A., Ackermann, Markus, Ajello, Marco, Baldini, Luca, Ballet, Jean, Barbiellini, Guido, Bastieri, Denis, Bellazzini, Ronaldo, Blandford, Roger D., Bloom, Elliott D., Bonamente, Emanuele, Ormes, Jonathan F., Reimer, Anita, Reimer, Olaf, Reposeur, Thierry, Borgland, Anders W., Ripken, Joachim, Romani, Roger W., Ziegler, Marcus, Roth, Marshall, Sadrozinski, Hartmut F. W., Ylinen, Tomi, Saz Parkinson, Pablo M., Sgrò, Carmelo, Siskind, Eric J., Smith, David A., Spinelli, Paolo, Strickman, Mark Samuel, Bouvier, Aurelien, Suson, Daniel Jeffrey, Brigida, Monica, Takahashi, Hiromitsu, Buson, Sara, Takahashi, Tadayuki, Tanaka, Takaaki, Thayer, Jana B., Thayer, John Gregg, Tibaldo, Luigi, Torres, Diego F., Tosti, Gino, Tramacere, Andrea, Brandt, Theresa J., Bruel, Philippe, Caliandro, Giuseppe Andrea, Uchiyama, Yasunobu, Usher, Tracy L., Vasileiou, Vlasios, Venter, Christo, Vilchez, Nicolás, Vitale, Vincenzo, Waite, Anthony P., Wang, Ping, Webb, Natalie, Winer, Brian L., Cameron, Robert A., Buehler, Rolf, Bregeon, Jean, Yang, Zhaoyu, Caraveo, Patrizia A., Carrigan, Svenja, Casandjian, Jean-Marc, Guillemot, Lucas, Charles, Eric, Chaty, Sylvain, Grove, J. Eric, Chekhtman, Alexandre, Cheung, C. C. Teddy, Chiang, James, Ciprini, Stefano, Claus, Rachel, Cohen-Tanugi, Johan, Conrad, Jan, DeCesar, Megan E., Guiriec, Sylvain, Dermer, Charles Dennison, Hays, Elizabeth, Palma, Francesco de, Digel, Seth W., Couto e Silva, Eduardo do, Drell, Persis S., Dubois, Richard, Dumora, Denis, Favuzzi, Cecilia, Fortin, Pascal, Frailis, Marco, Hadasch, Daniela, Jean, Pierre, Fukazawa, Yasushi, Fusco, Piergiorgio, Gargano, Fabio, Gasparrini, Dario, Gehrels, Neil, Germani, Stefano, Giglietto, Nicola, Giordano, Francesco, Glanzman, Tom, Godfrey, Gary, Johannesson, Gueolaugur, Harding, Alice K., Grenier, Isabelle A., Grondin, Marie-Hélène, Johnson, Tyrel J., Johnson, W. Neil, Kamae, Tuneyoshi, Parent, D., Katagiri, Hideaki, Kataoka, Jun, Pancrazi, Benoit, Kerr, Matthew, Knödlseder, Jürgen, Kuss, M., Lande, Joshua, Latronico, Luca, Lee, Shiu-Hang, Lemoine-Goumard, Marianne, Llena-Garde, Maja, Pepe, Monica, Longo, Francesco, Porter, Troy A., Loparco, Francesco, Lovellette, Michael N., Lubrano, Pasquale, Makeev, Andrey, Mazziotta, Mario Nicola, Michelson, Peter F., Mitthumsiri, Warit, Mizuno, Takafumi, Monte, Claudia, Pesce-Rollins, Melissa, Rainò, Silvia, Monzani, Maria Elena, Morselli, Aldo, Moskalenko, Igor V., Murgia, Simona, Naumann-Godo, Melitta, Nolan, Pat L., Norris, Jay P., Nuss, Eric, Ohsugi, Takashi, Omodei, Nicola, Rando, Riccardo, Piron, Frédéric, Orlando, Elena, Abdo, Aous A., Ackermann, Markus, Ajello, Marco, Baldini, Luca, Ballet, Jean, Barbiellini, Guido, Bastieri, Denis, Bellazzini, Ronaldo, Blandford, Roger D., Bloom, Elliott D., Bonamente, Emanuele, Ormes, Jonathan F., Reimer, Anita, Reimer, Olaf, Reposeur, Thierry, Borgland, Anders W., Ripken, Joachim, Romani, Roger W., Ziegler, Marcus, Roth, Marshall, Sadrozinski, Hartmut F. W., Ylinen, Tomi, Saz Parkinson, Pablo M., Sgrò, Carmelo, Siskind, Eric J., Smith, David A., Spinelli, Paolo, Strickman, Mark Samuel, Bouvier, Aurelien, Suson, Daniel Jeffrey, Brigida, Monica, Takahashi, Hiromitsu, Buson, Sara, Takahashi, Tadayuki, Tanaka, Takaaki, Thayer, Jana B., Thayer, John Gregg, Tibaldo, Luigi, Torres, Diego F., Tosti, Gino, Tramacere, Andrea, Brandt, Theresa J., Bruel, Philippe, Caliandro, Giuseppe Andrea, Uchiyama, Yasunobu, Usher, Tracy L., Vasileiou, Vlasios, Venter, Christo, Vilchez, Nicolás, Vitale, Vincenzo, Waite, Anthony P., Wang, Ping, Webb, Natalie, Winer, Brian L., Cameron, Robert A., Buehler, Rolf, Bregeon, Jean, Yang, Zhaoyu, Caraveo, Patrizia A., Carrigan, Svenja, Casandjian, Jean-Marc, Guillemot, Lucas, Charles, Eric, Chaty, Sylvain, Grove, J. Eric, Chekhtman, Alexandre, Cheung, C. C. Teddy, Chiang, James, Ciprini, Stefano, Claus, Rachel, Cohen-Tanugi, Johan, Conrad, Jan, DeCesar, Megan E., Guiriec, Sylvain, Dermer, Charles Dennison, Hays, Elizabeth, Palma, Francesco de, Digel, Seth W., Couto e Silva, Eduardo do, Drell, Persis S., Dubois, Richard, Dumora, Denis, Favuzzi, Cecilia, Fortin, Pascal, Frailis, Marco, Hadasch, Daniela, Jean, Pierre, Fukazawa, Yasushi, Fusco, Piergiorgio, Gargano, Fabio, Gasparrini, Dario, Gehrels, Neil, Germani, Stefano, Giglietto, Nicola, Giordano, Francesco, Glanzman, Tom, Godfrey, Gary, Johannesson, Gueolaugur, Harding, Alice K., Grenier, Isabelle A., Grondin, Marie-Hélène, Johnson, Tyrel J., Johnson, W. Neil, Kamae, Tuneyoshi, Parent, D., Katagiri, Hideaki, Kataoka, Jun, Pancrazi, Benoit, Kerr, Matthew, Knödlseder, Jürgen, Kuss, M., Lande, Joshua, Latronico, Luca, Lee, Shiu-Hang, Lemoine-Goumard, Marianne, Llena-Garde, Maja, Pepe, Monica, Longo, Francesco, Porter, Troy A., Loparco, Francesco, Lovellette, Michael N., Lubrano, Pasquale, Makeev, Andrey, Mazziotta, Mario Nicola, Michelson, Peter F., Mitthumsiri, Warit, Mizuno, Takafumi, Monte, Claudia, Pesce-Rollins, Melissa, Rainò, Silvia, Monzani, Maria Elena, Morselli, Aldo, Moskalenko, Igor V., Murgia, Simona, Naumann-Godo, Melitta, Nolan, Pat L., Norris, Jay P., Nuss, Eric, Ohsugi, Takashi, Omodei, Nicola, Rando, Riccardo, Piron, Frédéric, and Orlando, Elena

Abstract

Globular clusters with their large populations of millisecond pulsars (MSPs) are believed to be potential emitters of high-energy gamma-ray emission. Our goal is to constrain the millisecond pulsar populations in globular clusters from analysis of gamma-ray observations. We use 546 days of continuous sky-survey observations obtained with the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope to study the gamma-ray emission towards 13 globular clusters. Steady point-like high-energy gamma-ray emission has been significantly detected towards 8 globular clusters. Five of them (47 Tucanae, Omega Cen, NGC 6388, Terzan 5, and M 28) show hard spectral power indices $(0.7 < \Gamma <1.4)$ and clear evidence for an exponential cut-off in the range 1.0-2.6 GeV, which is the characteristic signature of magnetospheric emission from MSPs. Three of them (M 62, NGC 6440 and NGC 6652) also show hard spectral indices $(1.0 < \Gamma < 1.7)$, however the presence of an exponential cut-off can not be unambiguously established. Three of them (Omega Cen, NGC 6388, NGC 6652) have no known radio or X-ray MSPs yet still exhibit MSP spectral properties. From the observed gamma-ray luminosities, we estimate the total number of MSPs that is expected to be present in these globular clusters. We show that our estimates of the MSP population correlate with the stellar encounter rate and we estimate 2600-4700 MSPs in Galactic globular clusters, commensurate with previous estimates. The observation of high-energy gamma-ray emission from a globular cluster thus provides a reliable independent method to assess their millisecond pulsar populations that can be used to make constraints on the original neutron star X-ray binary population, essential for understanding the importance of binary systems in slowing the inevitable core collapse of globular clusters.

Published
2010

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