H.E.S.S. is currently the most sensitive instrument in the very-high-energy (VHE E>100 GeV) gamma-ray domain and has revealed many new sources along the Galactic Plane, a significant fraction of which seems to be associated with energetic pulsars. HESS J1825-137 and Vela X are considered to be the prototypes of such sources, where the large VHE nebula results from the whole history of the pulsar wind and the supernova remnant host, both evolving in a complex interstellar medium. These nebulae have been shown to be offset from the pulsar position and, in the first case, a spectral steepening at increasing distance from the pulsar has been measured. In this context, we present the updated results on two previously published sources, namely HESS J1809-193 and HESS J1912+101, and the preliminary results on the newly discovered HESS J1356-645. These extended VHE sources are thought to be associated with the energetic pulsars PSR J1809-1917, PSR J1913+1011 and PSR J1357-6429, respectively. We shall discuss the properties of each source in the VHE regime, together with those measured in the radio and X-ray domains.
American Institute of Physics Conference Series
- Pub Date:
- December 2008
- Interstellar medium and nebulae in external galaxies;
- 4 pages, 6 figures, Submitted to Proceedings of "4th Heidelberg International Symposium on High Energy Gamma-Ray Astronomy 2008"