| Literature DB >> 21212318 |
M Tavani1, A Bulgarelli, V Vittorini, A Pellizzoni, E Striani, P Caraveo, M C Weisskopf, A Tennant, G Pucella, A Trois, E Costa, Y Evangelista, C Pittori, F Verrecchia, E Del Monte, R Campana, M Pilia, A De Luca, I Donnarumma, D Horns, C Ferrigno, C O Heinke, M Trifoglio, F Gianotti, S Vercellone, A Argan, G Barbiellini, P W Cattaneo, A W Chen, T Contessi, F D'Ammando, G DePris, G Di Cocco, G Di Persio, M Feroci, A Ferrari, M Galli, A Giuliani, M Giusti, C Labanti, I Lapshov, F Lazzarotto, P Lipari, F Longo, F Fuschino, M Marisaldi, S Mereghetti, E Morelli, E Moretti, A Morselli, L Pacciani, F Perotti, G Piano, P Picozza, M Prest, M Rapisarda, A Rappoldi, A Rubini, S Sabatini, P Soffitta, E Vallazza, A Zambra, D Zanello, F Lucarelli, P Santolamazza, P Giommi, L Salotti, G F Bignami.
Abstract
The well-known Crab Nebula is at the center of the SN1054 supernova remnant. It consists of a rotationally powered pulsar interacting with a surrounding nebula through a relativistic particle wind. The emissions originating from the pulsar and nebula have been considered to be essentially stable. Here, we report the detection of strong gamma-ray (100 mega-electron volts to 10 giga-electron volts) flares observed by the AGILE satellite in September 2010 and October 2007. In both cases, the total gamma-ray flux increased by a factor of three compared with the non-flaring flux. The flare luminosity and short time scale favor an origin near the pulsar, and we discuss Chandra Observatory x-ray and Hubble Space Telescope optical follow-up observations of the nebula. Our observations challenge standard models of nebular emission and require power-law acceleration by shock-driven plasma wave turbulence within an approximately 1-day time scale.Year: 2011 PMID： 21212318 DOI： 10.1126/science.1200083
Source DB: PubMed Journal: Science ISSN： 0036-8075 Impact factor: 47.728