EDP Sciences
Free access
Volume 435, Number 1, May III 2005
Page(s) L17 - L20
Section Letters
DOI http://dx.doi.org/10.1051/0004-6361:200500105

A&A 435, L17-L20 (2005)
DOI: 10.1051/0004-6361:200500105


Discovery of extended VHE gamma-ray emission from the asymmetric pulsar wind nebula in MSH 15-52 with HESS

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, 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, D. Emmanoulopoulos13, P. Espigat6, F. Feinstein9, P. Fleury10, G. Fontaine10, Y. Fuchs14, S. Funk1, Y. A. Gallant9, B. Giebels10, S. Gillessen1, J. F. Glicenstein15, P. Goret15, C. Hadjichristidis3, M. Hauser13, G. Heinzelmann5, G. Henri14, G. Hermann1, J. A. Hinton1, W. Hofmann1, M. Holleran16, D. Horns1, O. C. de Jager16, B. Khélifi1, Nu. Komin7, A. Konopelko1, 7, I. J. Latham3, R. Le Gallou3, A. Lemière6, M. Lemoine-Goumard10, N. Leroy10, T. Lohse7, O. Martineau-Huynh17, 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. Pelletier14, S. Pita6, G. Pühlhofer1, 13, 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. Saugé14, 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, H. J. Völk1 and S. J. Wagner13

1  Max-Planck-Institut für Kernphysik, Heidelberg, Germany
    e-mail: Bruno.Khelifi@mpi-hd.mpg.de
2  Yerevan Physics Institute, Armenia
3  University of Durham, Department of Physics, UK
4  Centre d'Étude Spatiale des Rayonnements, CNRS/UPS, Toulouse, France
5  Universität Hamburg, Institut für Experimentalphysik, Germany
6  APC, Paris, France
7  Institut für Physik, Humboldt-Universität zu Berlin, Germany
8  LUTH, UMR 8102 du CNRS, Observatoire de Paris, Section de Meudon, France
9  Groupe d'Astroparticules de Montpellier, IN2P3/CNRS, Université Montpellier II, France
10  Laboratoire Leprince-Ringuet, IN2P3/CNRS, École Polytechnique, Palaiseau, France
11  European Associated Laboratory for Gamma-Ray Astronomy, jointly supported by CNRS and MPG
12  Dublin Institute for Advanced Studies, Ireland
13  Landessternwarte, Königstuhl, Heidelberg, Germany
14  Laboratoire d'Astrophysique de Grenoble, INSU/CNRS, Université Joseph Fourier, France
15  DAPNIA/DSM/CEA, CE Saclay, Gif-sur-Yvette, France
16  Unit for Space Physics, North-West University, Potchefstroom, South Africa
17  Laboratoire de Physique Nucléaire et de Hautes Énergies, IN2P3/CNRS, Universités Paris VI & VII, France
18  Institut für Theoretische Physik, Lehrstuhl IV: Weltraum und Astrophysik, Ruhr-Universität Bochum, Germany
19  Institute of Particle and Nuclear Physics, Charles University, Prague, Czech Republic
20  University of Namibia, Windhoek, Namibia

(Received 2 March 2005 / Accepted 27 March 2005)

The Supernova Remnant MSH 15-52 has been observed in very high energy (VHE) $\gamma$-rays using the HESS 4-telescope array located in Namibia. A $\gamma$-ray signal is detected at the 25 sigma level during an exposure of 22.1 h live time. The image reveals an elliptically shaped emission region around the pulsar PSR B1509-58, with semi-major axis ~6' in the NW-SE direction and semi-minor axis ~2'. This morphology coincides with the diffuse pulsar wind nebula as observed at X-ray energies by ROSAT. The overall energy spectrum from 280 GeV up to 40 TeV can be fitted by a power law with photon index $\Gamma=2.27\pm0.03_{\textrm {\scriptsize\,stat}}\pm 0.20_{\textrm{\scriptsize\,syst}}$. The detected emission can be plausibly explained by inverse Compton scattering of accelerated relativistic electrons with soft photons.

Key words: gamma-rays: observations -- ISM: supernova remnants -- pulsar wind nebula -- ISM: individual objects: PSR B1509-58 -- ISM: individual objects: G 320.4-1.2

SIMBAD Objects

© ESO 2005