%0 Journal Article
%T Fermi LAT Observations of LS 5039
%+ Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112))
%+ Laboratoire Leprince-Ringuet (LLR)
%+ Laboratoire de Physique Théorique et Astroparticules (LPTA)
%+ Laboratoire d'Astrophysique de Grenoble (LAOG)
%+ Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG)
%+ Centre d'étude spatiale des rayonnements (CESR)
%A A. Abdo, A.
%A Ackermann, Markus
%A Ajello, Marco
%A Atwood, William B.
%A Axelsson, Magnus
%A Baldini, Luca
%A Ballet, Jean
%A Barbiellini, Guido
%A Bastieri, D.
%A Baughman, B. M.
%A Bechtol, K.
%A Bellazzini, R.
%A Berenji, B.
%A Blandford, R. D.
%A Bloom, E.D.
%A Bonamente, E.
%A Borgland, A.W.
%A Bregeon, J.
%A Brez, A.
%A Brigida, M.
%A Bruel, Pascal
%A Burnett, T.H.
%A Buson, S.
%A Caliandro, G. A.
%A Cameron, R. A.
%A Caraveo, P. A.
%A Casandjian, J.M.
%A Cavazzuti, E.
%A Cecchi, C.
%A Celik, O.
%A Chaty, S.
%A Chekhtman, A.
%A Cheung, C.C.
%A Chiang, J.
%A Ciprini, S.
%A Claus, R.
%A Cohen-Tanugi, J.
%A Cominski, L.R.
%A Conrad, J.
%A Corbel, S.
%A Corbet, R.
%A Cutini, S.
%A Dermer, C. D.
%A de Angelis, A.
%A de Palma, F.
%A Digel, S. W.
%A Do Couto E Silva, E.
%A Drell, P.S.
%A Dubois, R.
%A Dubus, G.
%A Dumora, D.
%A Farnier, C.
%A Favuzzi, C.
%A Fegan, S.J.
%A Focke, W.B.
%A Fortin, P.
%A Frailis, M.
%A Fukazawa, Y.
%A Funk, S.
%A Fusco, P.
%A Gargano, F.
%A Gasparrini, D.
%A Gehrels, N.
%A Germani, S.
%A Giebels, B.
%A Giglietto, N.
%A Giordano, F.
%A Glanzman, T.
%A Godfrey, G.
%A Grenier, I.A.
%A Grondin, M.H.
%A Grove, J.E.
%A Guillemot, L.
%A Guiriec, S.
%A Hanabata, Y.
%A Harding, A.K.
%A Hayashida, M.
%A Hays, E.
%A Hill, A.B.
%A Horan, D.
%A Hugues, R.E.
%A Jackson, M.S.
%A Jóhannesson, G.
%A Johnson, T. J.
%A Johnson, W. N.
%A Johnson, A.S.
%A Kamae, T.
%A Katagiri, H.
%A Kataoka, J.
%A Kawai, N.
%A Kerr, M.
%A Knödlseder, Jürgen
%A Kocian, M. L.
%A Kuehn, F.
%A Kuss, M.
%A Lande, J.
%A Larsson, S.
%A Latronico, L.
%A Lemoine-Goumard, M.
%A Longo, F.
%A Loparco, F.
%A Lott, B.
%A Lovellette, M.N.
%A Lubrano, P.
%A Madejski, G. M.
%A Makeev, A.
%A Marelli, M.
%A Mazziotta, M.N.
%A Mcenery, J.E.
%A Meurer, C.
%A Michelson, P.F.
%A Mitthumsiri, W.
%A Mizuno, T.
%A Moiseev, A.A.
%A Monte, C.
%A Monzani, M.E.
%A Morselli, A.
%A Moskalenko, I.V.
%A Murgia, S.
%A Nolan, P. L.
%A Norris, J. P.
%A Nuss, E.
%A Ohsugi, T.
%A Omodei, N.
%A Orlando, E.
%A Ormes, J.F.
%A Ozaki, M.
%A Paneque, D.
%A Panetta, J.H.
%A Parent, D.
%A Pelassa, V.
%A Pepe, M.
%A Pesce-Rollins, M.
%A Piron, F.
%A Porter, T.A.
%A Rainò, S.
%A Rando, R.
%A Ray, P.S.
%A Razzano, M.
%A Rea, N.
%A Reimer, A.
%A Reimer, O.
%A Reposeur, T.
%A Ritz, S.
%A Rochester, L.S.
%A Rodriguez, A.Y.
%A Romani, R.W.
%A Roth, M.
%A Ryde, F.
%A Sanchez, D.
%A Sander, A.
%A Saz Parkinson, P.M.
%A Scargle, J.D.
%A Sgrò, C.
%A Sierpowska-Bartosik, A.
%A Siskind, E.J.
%A Smith, D. A.
%A Smith, P. D.
%A Spandre, G.
%A Spinelli, P.
%A Strickman, M.S.
%A Suson, D.J.
%A Tajima, H.
%A Takahashi, H.
%A Takahashi, T.
%A Tanaka, T.
%A Tanaka, Y.
%A Thayer, J.B.
%A Thompson, D.J.
%A Tibaldo, L.
%A Torres, D.F.
%A Tosti, G.
%A Tramacere, A.
%A Uchiyama, Y.
%A Usher, T.L.
%A Vasileiou, V.
%A Venter, C.
%A Vilchez, N.
%A Vitale, V.
%A Waite, A. P.
%A Wallace, E.
%A Wang, P.
%A Winer, B. L.
%A Wood, K.S.
%A Ylinen, T.
%A Ziegler, M.
%Z 6 pages, 5 figures, accepted for publication in ApJ Letters. Contact authors: Adam B. Hill (adam.hill@obs.ujf-grenoble.fr), Richard Dubois (richard@slac.stanford.edu), Takaaki Tanaka (ttanaka@slac.stanford.edu), Robin Corbet (Robin.Corbet@nasa.gov)
%< avec comité de lecture
%@ 2041-8205
%J The Astrophysical journal letters
%I Bristol : IOP Publishing
%V 706
%P L56-L61
%8 2009-11-20
%D 2009
%Z 0910.5520
%R 10.1088/0004-637X/706/1/L56
%K binaries: close
%K gamma rays: observations
%K stars: variables: other
%K X-rays: binaries
%K X-rays: individual (LS 5039)
%Z Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE]
%Z Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE]Journal articles
%X The first results from observations of the high mass X-ray binary LS 5039 using the Fermi Gamma-ray Space Telescope data between 2008 August and 2009 June are presented. Our results indicate variability that is consistent with the binary period, with the emission being modulated with a period of 3.903 +/- 0.005 days; the first detection of this modulation at GeV energies. The light curve is characterized by a broad peak around superior conjunction in agreement with inverse Compton scattering models. The spectrum is represented by a power law with an exponential cutoff, yielding an overall flux (100 MeV - 300 GeV) of 4.9 +/- 0.5(stat) +/- 1.8(syst) x 10^-7 photon cm^-2 s^-1, with a cutoff at 2.1 +/- 0.3(stat) +/- 1.1(syst) GeV and photon index Gamma = 1.9 +/- 0.1(stat) +/- 0.3(syst). The spectrum is observed to vary with orbital phase, specifically between inferior and superior conjunction. We suggest that the presence of a cutoff in the spectrum may be indicative of magnetospheric emission similar to the emission seen in many pulsars by Fermi.
%G English
%Z Fermi-LAT
%L in2p3-00436279
%U https://hal.in2p3.fr/in2p3-00436279
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