1. Probing the extent of the non-thermal emission from the Vela X region at TeV energies with H.E.S.S
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Guy Pelletier, A. Förster, C. vanEldik, J. L. Skilton, P. M. Chadwick, Cameron B Rulten, S. Fegan, Svenja Carrigan, E. Birsin, J. Bolmont, Jim Hinton, S. Balenderan, M. A. Kastendieck, R. Kossakowski, M. J. Vorster, U. Menzler, P. Eger, J. Dyks, Daniel Sánchez, Gilles Henri, M. Panter, Michael Punch, M. Füßling, M. H. Grondin, Markus Holler, B. Glück, Konrad Bernlöhr, P. Espigat, Andreas Hillert, Denis Wouters, Pierre-Olivier Petrucci, Emmanuel Moulin, Felix Aharonian, G. Pühlhofer, B. Degrange, M. Tluczykont, J. Perez, G. Spengler, S. Kaufmann, R. delosReyes, A. Reimer, B. Peyaud, M. C. Medina, B. Giebels, Fabio Acero, H. Laffon, S. Vorobiov, D. Göring, S. Schwarzburg, M. Naumann-Godo, Thomas Lohse, R. White, Alexandre Marcowith, I. Oya, Jacek Niemiec, F. Stinzing, A. Djannati-Ataï, K. Valerius, M. K. Daniel, C. L. Naumann, J. F. Glicenstein, Olaf Reimer, Iurii Sushch, R. C. G. Chaves, A. Balzer, M. Mayer, Anna Szostek, F. Dubois, Tomasz Bulik, A. Fiasson, Christian Farnier, F. Feinstein, P. Hofverberg, D. Klochkov, M. PazArribas, M. Mohamed, M. Dalton, F. Sheidaei, Francois Brun, D. Parsons, D. Hampf, Dieter Horns, J. Mehault, C. Couturier, J. Brucker, M. Gajdus, Stefan Ohm, B. Opitz, A. Bochow, K. Egberts, Gavin Rowell, Guillaume Dubus, A. Lopatin, Catherine Boisson, S. Pita, A. A. Zdziarski, J. Conrad, Nu. Komin, A. Charbonnier, Vincent Marandon, Ullrich Schwanke, N. Nguyen, H. Gast, S. Heinz, C. Trichard, N. Maxted, H.-S. Zechlin, B. Khélifi, V. Sahakian, D. Nedbal, Anna Zajczyk, Joachim Ripken, A. Viana, P. deWilt, A. Cheesebrough, H. J. Dickinson, J.-P. Tavernet, G. Lamanna, K. Dutson, Alicja Wierzcholska, R. Steenkamp, M. V. Fernandes, W. Domainko, Julien Masbou, Stefan Wagner, Gisela Anton, Dirk Lennarz, M. deNaurois, K. Katarzyń ski, Heinrich J. Völk, T. Garrigoux, Regis Terrier, K. Kosack, Lukasz Stawarz, W. Kluź niak, Yvonne Becherini, P.P. Krüger, Y. A. Gallant, Andreas Quirrenbach, Christo Venter, Matteo Cerruti, F. Krayzel, C. Jahn, Christoph Deil, T. Kneiske, M. Dyrda, U. F. Katz, G. Maurin, E. deOñ aWilhelmi, R. Moderski, Reinhard Schlickeiser, P. Vincent, A. Zech, K. Stycz, G. Hermann, S. J. Nolan, Werner Hofmann, Michał Ostrowski, P. Brun, Michael Zacharias, S. Schwemmer, L. Rob, A. Schulz, Anna Barnacka, Andrea Santangelo, Joachim Hahn, J. D. Hague, Francesca Volpe, Marek Jamrozy, D. Fernandez, Helene Sol, L. O'c. Drury, J. Harris, Martin Ward, L. Fallon, G. Vasileiadis, A. Jacholkowska, G. Fontaine, J. Becker Tjus, N. W. Pekeur, Martin Raue, G. Heinzelmann, J. Biteau, I. D. Davids, S. Häffner, T.J.L. McCom, G. Cologna, A. Abramowski, M. Renaud, Chia-Chun Lu, S. Rosier-Lees, Sabrina Casanova, A. G. Akhperjanian, C. Stegmann, I. Jung, B. Rudak, Frank M. Rieger, J. P. Lenain, P. Bordas, Laboratoire Univers et Particules de Montpellier (LUPM), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), HESS, Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université 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), Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), APC - Astrophysique des Hautes Energies (APC - AHE), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO), and Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules)
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[PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE] ,Ciencias Físicas ,Astrophysics::High Energy Astrophysical Phenomena ,individual objects: HESS J0835 [ISM] ,FOS: Physical sciences ,Vela X (pulsar) ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,individual objects: Vela X [ISM] ,Vela ,01 natural sciences ,HESS J0835–455 ,purl.org/becyt/ford/1 [https] ,Pulsar ,0103 physical sciences ,ROSAT ,Radiation mechanisms ,Surface brightness ,Sensitivity (control systems) ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,Non thermal mechanisms ,[PHYS]Physics [physics] ,Nebula ,010308 nuclear & particles physics ,[SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE] ,Gamma rays ,Order (ring theory) ,Astronomy and Astrophysics ,Radius ,purl.org/becyt/ford/1.3 [https] ,non-thermal [radiation mechanisms] ,Astrophysics - Astrophysics of Galaxies ,Astronomía ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,ddc:520 ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - High Energy Astrophysical Phenomena ,general [gamma rays] ,CIENCIAS NATURALES Y EXACTAS - Abstract
Context. Vela X is a region of extended radio emission in the western part of the Vela constellation: one of the nearest pulsar wind nebulae, and associated with the energetic Vela pulsar (PSR B0833-45). Extended very-high-energy (VHE) γ-ray emission (HESS J0835-455) was discovered using the H.E.S.S. experiment in 2004. The VHE γ-ray emission was found to be coincident with a region of X-ray emission discovered with ROSAT above 1.5 keV (the so-called Vela X cocoon): a filamentary structure extending southwest from the pulsar to the centre of Vela X. Aims. A deeper observation of the entire Vela X nebula region, also including larger offsets from the cocoon, has been performed with H.E.S.S. This re-observation was carried out in order to probe the extent of the non-thermal emission from the Vela X region at TeV energies and to investigate its spectral properties. Methods. To increase the sensitivity to the faint γ-ray emission from the very extended Vela X region, a multivariate analysis method combining three complementary reconstruction techniques of Cherenkov-shower images is applied for the selection of γ-ray events. The analysis is performed with the On/Off background method, which estimates the background from separate observations pointing away from Vela X; towards regions free of γ-ray sources but with comparable observation conditions. Results. The γ-ray surface brightness over the large Vela X region reveals that the detection of non-thermal VHE γ-ray emission from the PWN HESS J0835-455 is statistically significant over a region of radius 1.2° around the position α = 08 h35m00s, δ = - 45°36′00′′ (J2000). The Vela X region exhibits almost uniform γ-ray spectra over its full extent: the differential energy spectrum can be described by a power-law function with a hard spectral index Γ = 1.32 ± 0.06stat ± 0.12sys and an exponential cutoff at an energy of (14.0 ± 1.6stat ± 2.6sys) TeV. Compared to the previous H.E.S.S. observations of Vela X the new analysis confirms the general spatial overlap of the bulk of the VHE γ-ray emission with the X-ray cocoon, while its extent and morphology appear more consistent with the (more extended) radio emission, contradicting the simple correspondence between VHE γ-ray and X-ray emissions. Morphological and spectral results challenge the interpretation of the origin of γ-ray emission in the GeV and TeV ranges in the framework of current models. © ESO, 2012. Fil: Abramowski, A.. Universitat Hamburg; Alemania Fil: Aharonian, Felix A.. Max Planck Institut Fur Kernphysik; Alemania Fil: Akhperjanian, A. G.. National Academy Of Sciences Of The Republic Of Armenia; Armenia. Yerevan Physics Institute; Armenia Fil: Anton, G.. Universitat Erlangen-Nuremberg; Alemania Fil: Balenderan, S.. University Of Durham; Reino Unido Fil: Balzer, A.. Universitat Erlangen-Nuremberg; Alemania Fil: Barnacka, A.. CEA Saclay; Francia Fil: Becherini, Y.. Université Paris Diderot - Paris 7; Francia Fil: Becker Tjus, J.. Ruhr Universität Bochum; Alemania Fil: Bernlöhr, K.. Max Planck Institut Fur Kernphysik; Alemania Fil: Birsin, E.. Humboldt-universitat Zu Berlin; Alemania Fil: Bochow, A.. Max Planck Institut Fur Kernphysik; Alemania Fil: Boisson, C.. Université Paris Diderot - Paris 7; Francia Fil: Bolmont, J.. Max Planck Institut Fur Kernphysik; Alemania Fil: Boisson, C.. Université Paris Diderot - Paris 7; Francia Fil: Bolmont, J.. Universite Pierre et Marie Curie; Francia Fil: Brun, P.. Cea Saclay; Fil: Brun, F.. Laboratoire Leprince-ringuet; Francia Fil: Casanova, S.. Max Planck Institut Fur Kernphysik; Alemania Fil: Cerruti, M.. Université Paris Diderot - Paris 7; Francia Fil: Chadwick, P.M.. University Of Durham; Reino Unido Fil: Charbonnier, A.. Universite Pierre et Marie Curie; Francia Fil: Chaves, R.C.G.. Cea Saclay; Francia. Max Planck Institut Fur Kernphysik; Alemania Fil: Cheesebrough, A.. University Of Durham; Reino Unido Fil: Cologna, G.. Landessternwarte Heidelberg; Alemania Fil: Medina, Maria Clementina. Cea Saclay; Francia. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; Argentina
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- 2012
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