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11 results on '"Grondin, Marie-Hélène"'

1. Incremental Fermi Large Area Telescope Fourth Source Catalog

Author

collaboration, Fermi-LAT, Abdollahi, Soheila, Acero, Fabio, Baldini, Luca, Ballet, Jean, Bastieri, Denis, Bellazzini, Ronaldo, Berenji, Bijan, Berretta, Alessandra, Bissaldi, Elisabetta, Blandford, Roger D., Bloom, Elliott, Bonino, Raffaella, Brill, Ari, Britto, Richard J., Bruel, Philippe, Burnett, Toby H., Buson, Sara, Cameron, Rob A., Caputo, Regina, Caraveo, Patrizia A., Castro, Daniel, Chaty, Sylvain, Cheung, Teddy C., Chiaro, Graziano, Cibrario, Nicolo, Ciprini, Stefano, Coronado-Blazquez, Javier, Crnogorcevic, Milena, Cutini, Sara, D'Ammando, Filippo, De Gaetano, Salvatore, Digel, Seth W., Di Lalla, Niccolo, Dirirsa, Feraol F., Di Venere, Leonardo, Dominguez, Alberto, Ramazani, Vandad Fallah, Fegan, Stephen J., Ferrara, Elizabeth C., Fiori, Alessio, Fleischhack, Henrike, Franckowiak, Anna, Fukazawa, Yasushi, Funk, Stefan, Fusco, Piergiorgio, Galanti, Giorgio, Gammaldi, Viviana, Gargano, Fabio, Garrappa, Simone, Gasparrini, Dario, Giacchino, Federica, Giglietto, Nico, Giordano, Francesco, Giroletti, Marcello, Glanzman, Thomas, Green, David, Grenier, Isabelle A., Grondin, Marie-Helene, Guillemot, Lucas, Guiriec, Sylvain, Gustafsson, Michael, Harding, Alice K., Hays, Liz, Hewitt, John W., Horan, Deirdre, Hou, Xian, Johannesson, Gudlaugur, Karwin, Christopher M., Kayanoki, Taishu, Kerr, Matthew T., Kuss, Michael, Landriu, David, Larsson, Stefan, Latronico, Luca, Lemoine-Goumard, Marianne, Li, Jian, Liodakis, Ioannis, Longo, Francesco, Loparco, Francesco, Lott, Benoit, Lubrano, Pasquale, Maldera, Simone, Malyshev, Dmitry, Manfreda, Alberto, Marti-Devesa, Guillem, Mazziotta, Mario N., Mereu, Isabella, Meyer, Manuel, Michelson, Peter F., Mirabal, Nestor, Mitthumsiri, Warit, Mizuno, Tsunefumi, Moiseev, Alex A., Monzani, Maria E., Morselli, Aldo, Moskalenko, Igor V., Negro, Michela, Nuss, Eric, Omodei, Nicola, Orienti, Monica, Orlando, Elena, Paneque, David, Pei, Zhiyuan, Perkins, Jeremy S., Persic, Massimo, Pesce-Rollins, Melissa, Petrosian, Vahe, Pillera, Roberta, Poon, Helen, Porter, Troy A., Principe, Giacomo, Raino, Silvia, Rando, Riccardo, Rani, Bindu, Razzano, Massimiliano, Razzaque, Soebur, Reimer, Anita, Reimer, Olaf, Reposeur, Thierry, Sanchez-Conde, Miguel A., Parkinson, Pablo M. Saz, Scotton, Lorenzo, Serini, Davide, Sgro, Carmelo, Siskind, Eric J., Smith, David A., Spandre, Gloria, Spinelli, Paolo, Sueoka, Kohei, Suson, Dan J., Tajima, Hiro, Tak, Dongguen, Thayer, Jana B., Thompson, David J., Torres, Diego F., Troja, Eleonora, Valverde, Janeth, Wood, Kent, and Zaharijas, Gabrijela

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

We present an incremental version (4FGL-DR3, for Data Release 3) of the fourth Fermi-LAT catalog of gamma-ray sources. Based on the first twelve years of science data in the energy range from 50 MeV to 1 TeV, it contains 6658 sources. The analysis improves on that used for the 4FGL catalog over eight years of data: more sources are fit with curved spectra, we introduce a more robust spectral parameterization for pulsars, and we extend the spectral points to 1 TeV. The spectral parameters, spectral energy distributions, and associations are updated for all sources. Light curves are rebuilt for all sources with 1 yr intervals (not 2 month intervals). Among the 5064 original 4FGL sources, 16 were deleted, 112 are formally below the detection threshold over 12 yr (but are kept in the list), while 74 are newly associated, 10 have an improved association, and seven associations were withdrawn. Pulsars are split explicitly between young and millisecond pulsars. Pulsars and binaries newly detected in LAT sources, as well as more than 100 newly classified blazars, are reported. We add three extended sources and 1607 new point sources, mostly just above the detection threshold, among which eight are considered identified, and 699 have a plausible counterpart at other wavelengths. We discuss degree-scale residuals to the global sky model and clusters of soft unassociated point sources close to the Galactic plane, which are possibly related to limitations of the interstellar emission model and missing extended sources., Comment: accepted in ApJS; follow-up paper to 1902.10045

Published
2022
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2. High-energy gamma-ray study of the dynamically young SNR G150.3+4.5

Author

Devin, Justine, Lemoine-Goumard, Marianne, Grondin, Marie-Hélène, Castro, Daniel, Ballet, Jean, Cohen, Jamie, and Hewitt, John W.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The supernova remnant (SNR) G150.3+4.5 was recently discovered in the radio band; it exhibits a shell-like morphology with an angular size of $\sim 3^{\circ}$, suggesting either an old or a nearby SNR. Extended $\gamma$-ray emission spatially coincident with the SNR was reported in the Fermi Galactic Extended Source Catalog, with a power-law spectral index of $\Gamma$ = 1.91 $\pm$ 0.09. Studying particle acceleration in SNRs through their $\gamma$-ray emission is of primary concern to assess the nature of accelerated particles and the maximum energy they can reach. Using more than ten years of Fermi-LAT data, we investigate the morphological and spectral properties of the SNR G150.3+4.5 from 300 MeV to 3 TeV. We use the latest releases of the Fermi-LAT catalog, the instrument response functions and the Galactic and isotropic diffuse emissions. We use ROSAT all-sky survey data to assess any thermal and nonthermal X-ray emission, and we derive minimum and maximum distance to G150.3+4.5. We describe the $\gamma$-ray emission of G150.3+4.5 by an extended component which is found to be spatially coincident with the radio SNR. The spectrum is hard and the detection of photons up to hundreds of GeV points towards an emission from a dynamically young SNR. The lack of X-ray emission gives a tight constraint on the ambient density $n_0 \leq 3.6 \times 10^{-3}$ cm$^{-3}$. Since G150.3+4.5 is not reported as a historical SNR, we impose a lower limit on its age of $t$ = 1 kyr. We estimate its distance to be between 0.7 and 4.5 kpc. We find that G150.3+4.5 is spectrally similar to other dynamically young and shell-type SNRs, such as RX J1713.7$-$3946 or Vela Junior. The broadband nonthermal emission is explained with a leptonic scenario, implying a downstream magnetic field of $B = 5$ $\mu$G and acceleration of particles up to few TeV energies.

Published
2020
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3. Observing and modeling the gamma-ray emission from pulsar/pulsar wind nebula complex PSR J0205+6449/3C 58

Author

Li, Jian, Torres, Diego F., Lin, Ting Ting, Grondin, Marie-Helene, Kerr, Matthew, Lemoine-Goumard, Marianne, and Wilhelmi, Emma de Ona

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

We present the results of the analysis of 8 years of Fermi-LAT data of the pulsar/pulsar wind nebula complex PSR J0205+6449/3C 58. Using a contemporaneous ephemeris, we carried out a detailed analysis of PSR J0205+6449 both during its off-peak and on-peak phase intervals. 3C 58 is significantly detected during the off-peak phase interval. We show that the spectral energy distribution at high energies is the same disregarding the phases considered, and thus that this part of the spectrum is most likely dominated by the nebula radiation. We present results of theoretical models of the nebula and the magnetospheric emission that confirm this interpretation. Possible high-energy flares from 3C 58 were searched for, but none was unambiguously identified., Comment: 16 pages, 5 figures, 1 table; Accepted for publication in ApJ

Published
2018
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4. Towards a common analysis framework for gamma-ray astronomy

Author

Knödlseder, Jürgen, Mayer, Michael, Deil, Christoph, Schulz, Anneli, Grondin, Marie-Hélène, Martin, Pierrick, and Brau-Nogué, Sylvie

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract

Thanks to the success of current gamma-ray telescopes (Fermi, H.E.S.S., MAGIC, VERITAS), and in view of the prospects of planned observatories such as the Cherenkov Telescope Array (CTA) or the High-Altitude Water Cherenkov Observatory (HAWC), gamma-ray astronomy is becoming an integral part of modern astrophysical research. Analysis today relies on a large diversity of tools and software frameworks that were specifically and independently developed for each instrument. With the aim of unifying the analysis of gamma-ray data, we are currently developing GammaLib (http://sourceforge.net/projects/gammalib), a C++ library interfaced to Python that provides a framework for an instrument independent analysis of gamma-ray data. On top of GammaLib we have created ctools (http://cta.irap.omp.eu/ctools), a set of analysis executables that is being developed as one of the prototypes for the CTA high-level science analysis framework, but which is equally suited for the analysis of gamma-ray data from the existing Fermi-LAT telescope and current Cherenkov telescope arrays. In particular, ctools and GammaLib provide the novel opportunity of a simultaneous multi-instrument analysis. We present the status of the software development, and illustrate its capabilities with a spectral analysis of the Crab nebula emission over seven decades in energy (1 MeV to 10 TeV) using multi-instrument (COMPTEL, Fermi-LAT, H.E.S.S.) gamma-ray observations as well as a simulation of a CTA observation of the supernova remnant RX J1713.7-3946., Comment: In Proceedings of the 33rd International Cosmic Ray Conference (ICRC2013), Rio de Janeiro (Brazil). All CTA contributions at arXiv:1307.2232

Published
2013

5. Search for Spatially Extended Fermi-LAT Sources Using Two Years of Data

Author

Lande, Joshua, Ackermann, Markus, Allafort, Alice, Ballet, Jean, Bechtol, Keith, Burnett, Toby, Cohen-Tanugi, Johann, Drlica-Wagner, Alex, Funk, Stefan, Giordano, Francesco, Grondin, Marie-Helene, Kerr, Matthew, and Lemoine-Goumard, Marianne

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Spatial extension is an important characteristic for correctly associating gamma-ray-emitting sources with their counterparts at other wavelengths and for obtaining an unbiased model of their spectra. We present a new method for quantifying the spatial extension of sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi). We perform a series of Monte Carlo simulations to validate this tool and calculate the LAT threshold for detecting the spatial extension of sources. We then test all sources in the second Fermi-LAT catalog (2FGL) for extension. We report the detection of seven new spatially extended sources.

Published
2012
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6. Revisiting the PeVatron candidate MGRO J1908+06 with an updated H.E.S.S. analysis

Author

Abdalla, Hassan, Aharonian, Felix, Barbosa Martins, Victor, Lohse, Thomas, Luashvili, Anna, Lypova, Iryna, Mackey, Jonathan, Majumdar, Jhilik, Malyshev, Denys, MALYSHEV, Dmitry, Marandon, Vincent, Marchegiani, Paolo, Marcowith, Alexandre, Barnacka, Anna, Mares, Arnaud, Marti'i-Devesa, Guillem, Marx, Ramin, Maurin, Gilles, Meintjes, Pieter, Meyer, Manuel, Moderski, Rafal, Mohrmann, Lars, de Ona Wilhelmi, E., Joshi, Vikas, Barnard, Monica, Mitchell, Alison, Montanari, Alessandro, Moore, Chris, Morris, Paul, Moulin, Emmanuel, Muller, Jacques, Murach, Thomas, Nakashima, Kaori, Naurois , Mathieu, Nayerhoda, Amid, Batzofin, Rowan, Ndiyavala, Hambeleleni, Niemiec, Jacek, Noel, Angel, O'Brien, Paul, Oberholzer, Laenita Lorraine, Ohm, Stefan, Khelifi, Bruno, Giunti, Luca, Olivera-Nieto, Laura, de Ona Wilhelmi, Emma Maria, Becherini, Yvonne, Ostrowski, Michal, Panny, Sebastian, Panter, Michael, Parsons, Dan, Peron, Giada, Pita, Santiago, Poireau, Vincent, Prokhorov, Dmitry, Prokoph, Heike, PUEHLHOFER, Gerd, Berge, David, Punch, Michael, Quirrenbach, Andreas, Reichherzer, Patrick, Reimer, Anita, Reimer, Olaf, Remy, Quentin, Renaud, Matthieu, Reville, Brian, Rieger, Frank, Romoli, Carlo, Bernloehr, Konrad, Rowell, Gavin, Rudak, Bronislaw, Rueda Ricarte, Hector, Ruiz Velasco, Edna, Sahakian, Vardan, Sailer, Simon, Salzmann, Heiko, Sanchez, David, Santangelo, Andrea, Sasaki, Manami, Bi, Baiyang, Schaefer, Johannes, Schutte, Hester, Schwanke, Ullrich, Schüssler, Fabian, Senniappan, Mohanraj, Seyffert, Albert, Shapopi, Jimmy N. S., Shiningayamwe, Kleopas, Simoni, Rachel, Sinha, Atreyee, Boettcher, Markus, Sol, Helene, Spackman, Hugh, Specovius, Andreas, Spencer, Samuel Timothy, Spir-Jacob, Marion, Stawarz, Lukasz, Steenkamp, Riaan, Stegmann, Christian, Steinmassl, Simon, Steppa, Constantin, Boisson, Catherine, Sun, Lei, Takahashi, Tadayuki, Tanaka, Takaaki, Tavernier, Thomas, Taylor, Andrew, Terrier, Regis, Thiersen, Hannes, Thorpe-Morgan, Charles, Tluczykont, Martin, Tomankova, Lenka, Ait-Benkhali, Faical, Bolmont, Julien, Tsirou, Michelle, Tsuji, Naomi, Tuffs, Richard, Uchiyama, Yasunobu, van der Walt, Johann, van Eldik, Christopher, van Rensburg, Carlo, van Soelen, Brian, Vasileiadis, George, Veh, Johannes, Bony , Mathieu, Venter, Christo, Vincent, Pascal, Vink, Jacco, Völk, Heinrich J., Wagner, Stefan, Watson, Jason John, Werner, Felix, White, Richard, Wierzcholska, Alicja, Wong, Yu Wun, Breuhaus, Mischa, Yassin, Hend, Yusafzai, Anke, Zacharias, Michael, Zanin, Roberta, Zargaryan, Davit, Zdziarski, Andrzej, Zech, Andreas, Zhu, Sylvia Jiechen, Zmija, Andreas, Zouari, Samuel, Brose, Robert, Zywucka, Natalia, H. E. S. S. Collaboration, Brun, Francois, Bulik, Tomasz, Bylund, Thomas, Cangemi, Floriane, Caroff, Sami, Casanova, Sabrina, Anguener, Oguzhan, Catalano, Jaqueline, Chambery, Pauline, Chand, Tej Bahadur, Chen, Andrew, Cotter, Garret, Curlo, Malgorzata, Dalgleish, Hannah, Mbarubucyeye, Jean Damascene, Davids, Isak Delberth, Davies, James, Arcaro, Cornelia, Devin, Justine, Djannati-Ataï, Arache, Dmytriiev, Anton, Donath, Axel, Doroshenko, Victor, Dreyer, Lente, Du Plessis, Louis, Duffy, Connor, Egberts, Kathrin, Einecke, Sabrina, Armand, Celine, ERNENWEIN, Jean-Pierre, Fegan, Steven, Feijen, Kirsty, Fiasson, Armand, Fichet de Clairfontaine, Gaëtan, Fontaine, Gerard, Frans, Lott, Füssling, Matthias, Funk, Stefan, Gabici, Stefano, Armstrong, Tom, Gallant, Yves, Giavitto, Gianluca, Glawion, Dorit, Glicenstein, Jean-Francois, Grondin, Marie-Hélène, Hattingh, Sumari, Haupt, Maria, HERMANN, German, Hinton, Jim, Hofmann, Werner, Ashkar, Halim, Hoischen, Clemens, Holch, Tim Lukas, Holler, Markus, Horns, Dieter, Huang, Zhiqiu, Huber, David, Hörbe, Mario, Jamrozy, Marek, Jankowsky, Felix, JUNG, Ira, Backes, Michael, Kasai, Eli, Katarzynski, Krzysztof, Katz, Ulì, Khangulyan, Dmitry, Klepser, Stefan, Kluzniak, Wlodek, Komin, Nukri, Konno, Ruslan, Kosack, Karl, Kostiunin, Dmitriy, Baghmanyan, Vardan, Kreter, Michael, Kukec Mezek, Gašper, Kundu, Anu, Lamanna, Giovanni, Le Stum, Sébastien, Lemiere, Anne, Lemoine-Goumard, Marianne, Lenain, Jean-Philippe, Leuschner, Fabian, Levy, Christelle, AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), 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 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), H.E.S.S., Naurois , Mathieu, Bony , Mathieu, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Photon, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Cosmic ray, Astrophysics, emission [photon], Acceleration, Pulsar, photon: emission, emission [gamma ray], Angular resolution, ddc:530, galaxy [gamma ray], Supernova remnant, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), gamma ray: galaxy, energy: high, cosmic radiation: propagation, Molecular cloud, gamma ray: emission, 13. Climate action, cosmic radiation: galaxy, Milagro, HESS - Abteilung Hinton, high [energy], galaxy [cosmic radiation], propagation [cosmic radiation], Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

37th International Cosmic Ray Conference, ICRC 2021, Berlin, Germany - Online, 12 Jul 2021 - 23 Jul 2021; Proceedings of Science / International School for Advanced Studies (ICRC2021), 779 (2021). doi:10.22323/1.395.0779, Detecting and studying galactic gamma-ray sources emitting very-high energy photons sheds light on the acceleration and propagation of cosmic rays presumably created in these sources. Currently, there are few sources emitting photons with energies exceeding 100 TeV. In this work we revisit the unidentified source MGRO J1908+06, initially detected by Milagro, using an updated H.E.S.S. dataset and analysis pipeline. The vicinity of the source contains a supernova remnant and pulsars as well as molecular clouds. This makes the identification of the primary source(s) of galactic cosmic rays as well as the nature of the gamma-ray emission challenging, especially in light of the recent HAWC and LHAASO detection of the high energy tail of its spectrum. Exploiting the better angular resolution as compared to particle detectors, we investigate the morphology of the source as well as its spectral properties., Published by SISSA, Trieste

Published
2021
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7. Observation of burst activity from SGR1935+2154 associated to first galactic FRB with H.E.S.S

Author

Abdalla, Hassan, Aharonian, Felix, Barbosa Martins, Victor, Lenain, Jean-Philippe, Leuschner, Fabian, Levy, Christelle, Lohse, Thomas, Luashvili, Anna, Lypova, Iryna, Mackey, Jonathan, Majumdar, Jhilik, Malyshev, Denys, Malyshev, Dmitry, Barnacka, Anna, Marandon, Vincent, Marchegiani, Paolo, Marcowith, Alexandre, Mares, Arnaud, Martí-Devesa, Guillem, Marx, Ramin, Maurin, Gilles, Meintjes, Pieter, Meyer, Manuel, Mitchell, Alison, Barnard, Monica, Moderski, Rafal, Mohrmann, Lars, Montanari, Alessandro, Moore, Chris, Morris, Paul, Moulin, Emmanuel, Muller, Jacques, Murach, Thomas, Nakashima, Kaori, Naurois , Mathieu, Batzofin, Rowan, Nayerhoda, Amid, Davids, Hambeleleni, Niemiec, Jacek, Noel, Angel, O'Brien, Paul, Oberholzer, Laenita Lorraine, Ohm, Stefan, Olivera-Nieto, Laura, Ona-Wilhelmi , Emma, Ostrowski, Michal, Becherini, Yvonne, Panny, Sebastian, Panter, Michael, Parsons, Dan, Peron, Giada, Pita, Santiago, Poireau, Vincent, Prokhorov, Dmitry, Prokoph, Heike, PUEHLHOFER, Gerd, Punch, Michael, Berge, David, Quirrenbach, Andreas, Reichherzer, Patrick, Reimer, Anita, Reimer, Olaf, Remy, Quentin, Renaud, Matthieu, Reville, Brian, Rieger, Frank, Romoli, Carlo, Rowell, Gavin, Bernloehr, Konrad, Rudak, Bronislaw, Rueda Ricarte, Hector, Ruiz Velasco, Edna, Sahakian, Vardan, Sailer, Simon, Salzmann, Heiko, Sanchez, David, Santangelo, Andrea, Sasaki, Manami, Schaefer, Johannes, Bi, Baiyang, Schutte, Hester, Schwanke, Ullrich, Schüssler, Fabian, Senniappan, Mohanraj, Seyffert, Albert, Shapopi, Jimmy N. S., Shiningayamwe, Kleopas, Simoni, Rachel, Sinha, Atreyee, Sol, Helene, Böttcher, Markus, Spackman, Hugh, Specovius, Andreas, Spencer, Samuel Timothy, Spir-Jacob, Marion, Stawarz, Lukasz, Steenkamp, Riaan, Stegmann, Christian, Steinmassl, Simon, Steppa, Constantin, Sun, Lei, Boisson, Catherine, Takahashi, Tadayuki, Tanaka, Takaaki, Tavernier, Thomas, Taylor, Andrew, Terrier, Regis, Thiersen, Hannes, Thorpe-Morgan, Charles, Tluczykont, Martin, Tomankova, Lenka, Tsirou, Michelle, Ait-Benkhali, Faical, Bolmont, Julien, Tsuji, Naomi, Tuffs, Richard, Uchiyama, Yasunobu, van der Walt, Johann, van Eldik, Christopher, van Rensburg, Carlo, van Soelen, Brian, Vasileiadis, George, Veh, Johannes, Venter, Christo, Bony , Mathieu, Vincent, Pascal, Vink, Jacco, Völk, Heinrich J., Wagner, Stefan, Watson, Jason John, Werner, Felix, White, Richard, Wierzcholska, Alicja, Wong, Yu Wun, Yassin, Hend Mahmoud, Breuhaus, Mischa, Yusafzai, Anke, Zacharias, Michael, Zanin, Roberta, Zargaryan, Davit, Zdziarski, Andrzej, Zech, Andreas, Zhu, Sylvia, Zmija, Andreas, Zouari, Samuel, Żywucka, Natalia, Brose, Robert, H. E. S. S. Collaboration, Brun, Francois, Bulik, Tomasz, Bylund, Thomas, Cangemi, Floriane, Caroff, Sami, Casanova, Sabrina, Anguener, Oguzhan, Catalano, Jaqueline, Chambery, Pauline, Chand, Tej Bahadur, Chen, Andrew, Cotter, Garret, Curlo, Malgorzata, Dalgleish, Hannah, Damascene Mbarubucyeye, Jean, Davids, Isak Delberth, Davies, James, Arcaro, Cornelia, Devin, Justine, Djannati-Ataï, Arache, Dmytriev, Anton, Donath, Axel, Doroshenko, Victor, Dreyer, Lente, Du Plessis, Louis, Duffy, Connor, Egberts, Kathrin, Einecke, Sabrina, Armand, Celine, ERNENWEIN, Jean-Pierre, Fegan, Steven, Feijen, Kirsty, Fiasson, Armand, Fichet de Clairfontaine, Gaëtan, Fontaine, Gerard, Frans, Lott, Fuessling, Matthias, Funk, Stefan, Gabici, Stefano, Armstrong, Tom, Gallant, Yves, Giavitto, Gianluca, Giunti, Luca, Glawion, Dorit, Glicenstein, Jean-Francois, Grondin, Marie-Hélène, Hattingh, Sumari, Haupt, Maria, HERMANN, German, Hinton, Jim, Ashkar, Halim, Hofmann, Werner, Hoischen, Clemens, Holch, Tim, Holler, Markus, Horns, Dieter, Huang, Zhi-Qiu, Huber, David, Hörbe, Mario, Jamrozy, Marek, Jankowsky, Felix, Backes, Michael, Joshi, Vikas, JUNG, Ira, Kasai, Eli, Katarzynski, Krzysztof, Katz, Ulì, Khangulyan, Dmitry, Khelifi, Bruno, Klepser, Stefan, Kluzniak, Wlodek, Komin, Nukri, Baghmanyan, Vardan, Konno, Ruslan, Kosack, Karl, Kostiunin, Dmitriy, Kreter, Michael, Kukec Mezek, Gašper, Kundu, Anu, Lamanna, Giovanni, Le Stum, Sébastien, Lemiere, Anne, Lemoine-Goumard, Marianne, Naurois , Mathieu, Bony , Mathieu, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and H.E.S.S.

Subjects
Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Brightness, Astrophysics::High Energy Astrophysical Phenomena, atmosphere [Cherenkov counter], Soft gamma repeater, FOS: Physical sciences, burst [gamma ray], X-ray: burst, Astrophysics, gamma ray: burst, Cherenkov counter: atmosphere, Magnetar, Radio spectrum, Observational evidence, Pulsar, ddc:530, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - High Energy Astrophysical Phenomena, Cherenkov radiation, burst [X-ray]
Abstract

37th International Cosmic Ray Conference, ICRC2021, Berlin, Germany - Online, 12 Jul 2021 - 23 Jul 2021; Proceedings of Science / International School for Advanced Studies (ICRC2021), 777 (2021). doi:10.22323/1.395.0777, Fast radio bursts (FRB) are enigmatic powerful single radio pulses with durations of several milliseconds and high brightness temperatures suggesting coherent emission mechanism. For the time being a number of extragalactic FRBs have been detected in the high-frequency radio band including repeating ones. The most plausible explanation for these phenomena is magnetar hyperflares. The first observational evidence of this scenario was obtained in April 2020 when an FRB was detected from the direction of the Galactic magnetar and soft gamma repeater SGR1935+2154. The FRB was preceded with a number of soft gamma-ray bursts observed by Swift-BAT satellite, which triggered the follow-up program of the H.E.S.S. imaging atmospheric Cherenkov telescopes (IACTs). H.E.S.S. has observed SGR1935+2154 over a 2 hour window few hours prior to the FRB detection by STARE2 and CHIME. The observations overlapped with other X-ray bursts from the magnetar detected by INTEGRAL and Swift-BAT, thus providing first observations of a magnetar in a flaring state in the very-high energy domain. We present the analysis of these observations, discuss the obtained results and prospects of the H.E.S.S. follow-up program for soft gamma repeaters and anomalous X-ray pulsars., Published by SISSA, Trieste

Published
2021
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8. 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

9. Search for gamma-ray emission from magnetars with the Fermi Large Area Telescope

Author

Abdo, Aous A., Ackermann, Markus, Ajello, Marco, Allafort, Alice, Baldini, Luca, Ballet, Jean, Barbiellini, Guido, Baring, Matthew G., Bastieri, Denis, Bellazzini, Ronaldo, Blandford, Roger D., Longo, Francesco, Loparco, Francesco, Lovellette, Michael N., Lubrano, Pasquale, Makeev, Andrey, Marelli, Martino, Mazziotta, Mario Nicola, McEnery, Julie E., Mehault, Jeremie, Michelson, Peter F., Ritz, Steven, Piron, Frédéric, Mizuno, Takafumi, Moiseev, Alex A., Monte, Claudia, Monzani, Maria Elena, Morselli, Aldo, Moskalenko, Igor V., Murgia, Simona, Naumann-Godo, Melitta, Nolan, Pat L., Sadrozinski, Hartmut F. W., Nuss, Eric, Porter, Troy A., Ohsugi, Takashi, Okumura, Akira, Omodei, Nicola, Orlando, Elena, Ormes, Jonathan F., Ozaki, Masanobu, Paneque, David, Parent, D., Saz Parkinson, Pablo M., Pepe, Monica, Rainò, Silvia, Rando, Riccardo, Razzano, Massimiliano, Rea, Nanda, Reimer, Anita, Reimer, Olaf, Reposeur, Thierry, Bloom, Elliott D., Sgrò, Carmelo, Siskind, Eric J., Smith, David A., Spandre, Gloria, Spinelli, Paolo, Strickman, Mark Samuel, Takahashi, Hiromitsu, Cecchi, Claudia, Bonamente, Emanuele, Tanaka, Takaaki, Thayer, Jana B., Thompson, David J., Tibaldo, Luigi, Torres, Diego F., Tosti, Gino, Tramacere, Andrea, Troja, Eleonora, Uchiyama, Yasunobu, Çelik, Özlem, Usher, Tracy L., Borgland, Anders W., Vandenbroucke, Justin, Vasileiou, Vlasios, Vianello, Giacomo, Vitale, Vincenzo, Waite, Anthony P., Winer, Brian L., Wood, Kent S., Yang, Zhaoyu, Chaty, Sylvain, Ziegler, Marcus, Bouvier, Aurelien, Bregeon, Jean, Brigida, Monica, Bruel, Philippe, Burnett, Thompson H., Caliandro, Giuseppe Andrea, Cameron, Robert A., Caraveo, Patrizia A., Chekhtman, Alexandre, Cheung, C. C. Teddy, Chiang, James, Ciprini, Stefano, Claus, Rachel, Conrad, Jan, Hartogh, Paul, Johannesson, Gueolaugur, Dermer, Charles Dennison, Angelis, Alessandro de, Palma, Francesco de, Dib, Rim, Dormody, Michael, Couto e Silva, Eduardo do, Drell, Persis S., Dubois, Richard, Dumora, Denis, Enoto, Teruaki, Johnson, A. S., Favuzzi, Cecilia, Frailis, Marco, Fusco, Piergiorgio, Gargano, Fabio, Gehrels, Neil, Giglietto, Nicola, Giommi, Paolo, Giordano, Francesco, Giroletti, Marcello, Glanzman, Tom, Kaspi, Victoria M., Godfrey, Gary, Grenier, Isabelle A., Grondin, Marie-Hélène, Guiriec, Sylvain, Hadasch, Daniela, Hanabata, Yoshitaka, Harding, Alice K., Hays, Elizabeth, Israel, Gian Luca, Katagiri, Hideaki, Kataoka, Jun, Knödlseder, Jürgen, Kuss, M., Lande, Joshua, Lee, Shiu-Hang, Lemoine-Goumard, Marianne, Pesce-Rollins, Melissa, Abdo, Aous A., Ackermann, Markus, Ajello, Marco, Allafort, Alice, Baldini, Luca, Ballet, Jean, Barbiellini, Guido, Baring, Matthew G., Bastieri, Denis, Bellazzini, Ronaldo, Blandford, Roger D., Longo, Francesco, Loparco, Francesco, Lovellette, Michael N., Lubrano, Pasquale, Makeev, Andrey, Marelli, Martino, Mazziotta, Mario Nicola, McEnery, Julie E., Mehault, Jeremie, Michelson, Peter F., Ritz, Steven, Piron, Frédéric, Mizuno, Takafumi, Moiseev, Alex A., Monte, Claudia, Monzani, Maria Elena, Morselli, Aldo, Moskalenko, Igor V., Murgia, Simona, Naumann-Godo, Melitta, Nolan, Pat L., Sadrozinski, Hartmut F. W., Nuss, Eric, Porter, Troy A., Ohsugi, Takashi, Okumura, Akira, Omodei, Nicola, Orlando, Elena, Ormes, Jonathan F., Ozaki, Masanobu, Paneque, David, Parent, D., Saz Parkinson, Pablo M., Pepe, Monica, Rainò, Silvia, Rando, Riccardo, Razzano, Massimiliano, Rea, Nanda, Reimer, Anita, Reimer, Olaf, Reposeur, Thierry, Bloom, Elliott D., Sgrò, Carmelo, Siskind, Eric J., Smith, David A., Spandre, Gloria, Spinelli, Paolo, Strickman, Mark Samuel, Takahashi, Hiromitsu, Cecchi, Claudia, Bonamente, Emanuele, Tanaka, Takaaki, Thayer, Jana B., Thompson, David J., Tibaldo, Luigi, Torres, Diego F., Tosti, Gino, Tramacere, Andrea, Troja, Eleonora, Uchiyama, Yasunobu, Çelik, Özlem, Usher, Tracy L., Borgland, Anders W., Vandenbroucke, Justin, Vasileiou, Vlasios, Vianello, Giacomo, Vitale, Vincenzo, Waite, Anthony P., Winer, Brian L., Wood, Kent S., Yang, Zhaoyu, Chaty, Sylvain, Ziegler, Marcus, Bouvier, Aurelien, Bregeon, Jean, Brigida, Monica, Bruel, Philippe, Burnett, Thompson H., Caliandro, Giuseppe Andrea, Cameron, Robert A., Caraveo, Patrizia A., Chekhtman, Alexandre, Cheung, C. C. Teddy, Chiang, James, Ciprini, Stefano, Claus, Rachel, Conrad, Jan, Hartogh, Paul, Johannesson, Gueolaugur, Dermer, Charles Dennison, Angelis, Alessandro de, Palma, Francesco de, Dib, Rim, Dormody, Michael, Couto e Silva, Eduardo do, Drell, Persis S., Dubois, Richard, Dumora, Denis, Enoto, Teruaki, Johnson, A. S., Favuzzi, Cecilia, Frailis, Marco, Fusco, Piergiorgio, Gargano, Fabio, Gehrels, Neil, Giglietto, Nicola, Giommi, Paolo, Giordano, Francesco, Giroletti, Marcello, Glanzman, Tom, Kaspi, Victoria M., Godfrey, Gary, Grenier, Isabelle A., Grondin, Marie-Hélène, Guiriec, Sylvain, Hadasch, Daniela, Hanabata, Yoshitaka, Harding, Alice K., Hays, Elizabeth, Israel, Gian Luca, Katagiri, Hideaki, Kataoka, Jun, Knödlseder, Jürgen, Kuss, M., Lande, Joshua, Lee, Shiu-Hang, Lemoine-Goumard, Marianne, and Pesce-Rollins, Melissa

Abstract

We report on the search for 0.1-10 GeV emission from magnetars in 17 months of Fermi Large Area Telescope (LAT) observations. No significant evidence for gamma-ray emission from any of the currently known magnetars is found. The most stringent upper limits to date on their persistent emission in the Fermi energy range are estimated between ~10–12and10–10 erg s–1 cm–2, depending on the source. We also searched for gamma-ray pulsations and possible outbursts, also with no significant detection. The upper limits derived support the presence of a cutoff at an energy below a few MeV in the persistent emission of magnetars. They also show the likely need for a revision of current models of outer-gap emission from strongly magnetized pulsars, which, in some realizations, predict detectable GeV emission from magnetars at flux levels exceeding the upper limits identified here using the Fermi-LAT observations.

Published
2010

10. First detections of pulsar wind nebulae with the Fermi-Large Area Telescope and study of their pulsars

Author

Grondin, Marie-Hélène, David A. Smith(smith@cenbg.in2p3.fr), Thierry Montmerle (Président du jury), David A. Smith (Directeur de thèse), Marianne Lemoine-Goumard (Co-directrice de thèse), Jürgen Knödlseder (Rapporteur), Jean-Paul Tavernet (Rapporteur), Franck Gobet (Examinateur), David J. Thompson (Examinateur), Smith, David A, Lemoine-Goumard, Marianne, Gobet, Franck, Thompson, David J., Montmerle, Thierry, Knödlseder, Jürgen, Tavernet, Jean-Paul, and Grondin, Marie-Hélène

Subjects
Astronomie gamma de haute énergie, Large Area Telescope (LAT), pulsar wind nebulae (PWNe), spectral modeling, pulsars, nébuleuses de pulsars, High energy gamma-ray astronomy, modélisation spectrale, [SDU.ASTR] Sciences of the Universe [physics]/Astrophysics [astro-ph], Fermi
Abstract

The Fermi Gamma-ray Space Telescope was launched on 2008 June 11, carrying the Large Area Telescope (LAT), sensitive to gamma-rays in the 20 MeV – 300 GeV energy range. The Crab Nebula had been detected and studied in the 70 MeV – 30 GeV band using the CGRO-EGRET experiment, but no pulsar wind nebula (PWN) had ever been firmly identified in the high energy gamma-ray domain. PWNe are powered by the constant injection of a relativistic wind of electrons and positrons from their central pulsars. These charged particles are accelerated at the shock front forming the PWN and emit photons which can be observed along the entire electromagnetic spectrum, including the high energy gamma-ray domain. Data provided by the Fermi-LAT during the first two years of the mission have allowed the detection and the identification of three PWNe and their associated pulsars (Crab Nebula, Vela X and MSH 15-52) as well as the PWN HESS J1825-137 discovered by ground-based experiments sensitive to very high energy gamma-rays. Results of temporal, spectral and morphological analyses of the pulsar/PWN systems detected by Fermi-LAT, as well as results of systematic studies performed (i) around every gamma-ray pulsar detected by the LAT and (ii) around every very high energy source identified as a PWN or a PWN candidate are presented in this dissertation. These studies bring new insights and constraints on the physical properties of the sources as well as on emitting processes in pulsar magnetospheres and in PWNe., Dédié à l'étude de l'astronomie gamma, le satellite Fermi a été lancé le 11 juin 2008. Il comporte à son bord l'instrument Large Area Telescope (LAT), sensible au rayonnement gamma dans la gamme d'énergie de 20 MeV à 300 GeV. Bien que la nébuleuse du Crabe ait été étudiée dans la gamme d'énergie 70 MeV à 30 GeV couverte par son précédesseur, l'expérience CGRO-EGRET, aucune nébuleuse n'a jamais été clairement identifiée dans le domaine des rayons gamma de haute énergie jusqu'au lancement de Fermi. Les pulsars alimentent les nébuleuses qui les entourent par l'injection permanente d'un vent d'électrons et positrons relativistes qui, accélérés au niveau de l'onde de choc délimitant les nébuleuses de pulsars, émettent un rayonnement pouvant être observé dans les différents domaines du spectre électromagnétique, et notamment dans le domaine des rayons gamma de haute énergie. Les données recueillies par le Fermi-LAT au cours des deux premières années de mission ont désormais permis la détection et l'identification de trois nébuleuses et de leurs pulsars associés (nébuleuses du Crabe, de Vela-X et de MSH 15-52) ainsi que de la nébuleuse de pulsar HESS J1825-137 découverte par les instruments au sol dédiés à l'astronomie gamma de très haute énergie. Les résultats des analyses temporelle, spectrale et morphologique réalisées sur les systèmes pulsars/nébuleuses détectés par le LAT sont exposés dans ce manuscrit. La synthèse des études systématiques réalisées (i) dans les régions comportant un pulsar émetteur en rayons gamma et (ii) dans les régions comportant une source émettrice de rayons gamma de très haute énergie étant identifiée en tant que nébuleuse de pulsar ou candidate en tant que telle, sont également présentés dans cette thèse. Ces études apportent de nouvelles contraintes sur les propriétés physiques des sources ainsi que sur les mécanismes de rayonnement mis en jeu dans la magnétosphère des pulsars et au sein de leurs nébuleuses.

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