EDP Sciences
Free access
Volume 432, Number 2, March III 2005
Page(s) L25 - L29
Section Letters
DOI http://dx.doi.org/10.1051/0004-6361:200500022

A&A 432, L25-L29 (2005)
DOI: 10.1051/0004-6361:200500022


Very high energy gamma rays from the composite SNR G 0.9+0.1

F. Aharonian1, A. G. Akhperjanian2, K.-M. Aye3, A. R. Bazer-Bachi4, M. Beilicke5, W. Benbow1, D. Berge1, P. Berghaus6, K. Bernlöhr1, 7, C. Boisson8, O. Bolz1, C. Borgmeier7, I. Braun1, F. Breitling7, A. M. Brown3, J. Bussons Gordo9, P. M. Chadwick3, L.-M. Chounet10, R. Cornils5, L. Costamante1, 11, B. Degrange10, A. Djannati-Ataï6, L. O'C. Drury12, G. Dubus10, T. Ergin7, P. Espigat6, F. Feinstein9, P. Fleury10, G. Fontaine10, S. Funk1, Y. A. Gallant9, B. Giebels10, S. Gillessen1, P. Goret13, C. Hadjichristidis3, M. Hauser14, G. Heinzelmann5, G. Henri15, G. Hermann1, J. A. Hinton1, W. Hofmann1, M. Holleran16, D. Horns1, O. C. de Jager16, I. Jung1, 14, B. Khélifi1, Nu. Komin7, A. Konopelko1, 7, I. J. Latham3, R. Le Gallou3, A. Lemière6, M. Lemoine10, N. Leroy10, T. Lohse7, A. Marcowith4, C. Masterson1, 11, T. J. L. McComb3, M. de Naurois17, S. J. Nolan3, A. Noutsos3, K. J. Orford3, J. L. Osborne3, M. Ouchrif17, 11, M. Panter1, G. Pelletier15, S. Pita6, G. Pühlhofer1, 14, M. Punch6, B. C. Raubenheimer16, M. Raue5, J. Raux17, S. M. Rayner3, I. Redondo10, 11, A. Reimer18, O. Reimer18, J. Ripken5, L. Rob19, L. Rolland17, G. Rowell1, V. Sahakian2, L. Saugé15, S. Schlenker7, R. Schlickeiser18, C. Schuster18, U. Schwanke7, M. Siewert18, H. Sol8, R. Steenkamp20, C. Stegmann7, J.-P. Tavernet17, R. Terrier6, C. G. Théoret6, M. Tluczykont10, 11, G. Vasileiadis9, C. Venter16, P. Vincent17, B. Visser16, H. J. Völk1 and S. J. Wagner14

1  Max-Planck-Institut für Kernphysik, PO Box 103980, 69029 Heidelberg, Germany
    e-mail: Jim.Hinton@mpi-hd.mpg.de
2  Yerevan Physics Institute, 2 Alikhanian Brothers St., 375036 Yerevan, Armenia
3  University of Durham, Department of Physics, South Road, Durham DH1 3LE, UK
4  Centre d'Étude Spatiale des Rayonnements, CNRS/UPS, 9 Av. du Colonel Roche, BP 4346, 31029 Toulouse Cedex 4, France
5  Universität Hamburg, Institut für Experimentalphysik, Luruper Chaussee 149, 22761 Hamburg, Germany
6  Physique Corpusculaire et Cosmologie, IN2P3/CNRS, Collège de France, 11 place Marcelin Berthelot, 75231 Paris Cedex 05, France
7  Institut für Physik, Humboldt-Universität zu Berlin, Newtonstr. 15, 12489 Berlin, Germany
8  LUTH, UMR 8102 du CNRS, Observatoire de Paris, Section de Meudon, 92195 Meudon Cedex, France
9  Groupe d'Astroparticules de Montpellier, IN2P3/CNRS, Université Montpellier II, CC85, Place Eugène Bataillon, 34095 Montpellier Cedex 5, France
10  Laboratoire Leprince-Ringuet, IN2P3/CNRS, École Polytechnique, 91128 Palaiseau, France
11  European Associated Laboratory for Gamma-Ray Astronomy, jointly supported by CNRS and MPG
12  Dublin Institute for Advanced Studies, 5 Merrion Square, Dublin 2, Ireland
13  Service d'Astrophysique, DAPNIA/DSM/CEA, CE Saclay, 91191 Gif-sur-Yvette, France
14  Landessternwarte, Königstuhl, 69117 Heidelberg, Germany
15  Laboratoire d'Astrophysique de Grenoble, INSU/CNRS, Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 9, France
16  Unit for Space Physics, North-West University, Potchefstroom 2520, South Africa
17  Laboratoire de Physique Nucléaire et de Hautes Énergies, IN2P3/CNRS, Universités Paris VI & VII, 4 place Jussieu, 75231 Paris Cedex 05, France
18  Institut für Theoretische Physik, Lehrstuhl IV: Weltraum und Astrophysik, Ruhr-Universität Bochum, 44780 Bochum, Germany
19  Institute of Particle and Nuclear Physics, Charles University, V Holesovickach 2, 180 00 Prague 8, Czech Republic
20  University of Namibia, Private Bag 13301, Windhoek, Namibia

(Received 15 December 2004 / Accepted 11 January 2005)

Very high energy (>100 GeV) gamma-ray emission has been detected for the first time from the composite supernova remnant G 0.9+0.1 using the HESS$\,$ instrument. The source is detected with a significance of $\approx$$13\sigma$, and a photon flux above 200 GeV of ( $5.7\pm0.7_{\rm stat}\pm1.2_{\rm sys})\times10^{-12}$ cm-2 s-1, making it one of the weakest sources ever detected at TeV energies. The photon spectrum is compatible with a power law ( ${\rm d}N/{\rm d}E \propto E^{-\Gamma}$) with photon index $\Gamma = 2.40\pm0.11_{\rm stat}\pm0.20_{\rm sys}$. The gamma-ray emission appears to originate in the plerionic core of the remnant, rather than the shell, and can be plausibly explained as inverse Compton scattering of relativistic electrons.

Key words: ISM: supernova remnants -- ISM: individual objects: G 0.9+0.1 -- gamma-rays: observations

SIMBAD Objects

© ESO 2005