Discovery of powerful gamma-ray flares from the Crab Nebula

M. Tavani, 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. HornsC. 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. DeParis, 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

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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.
Original languageEnglish
Pages (from-to)736 - 739
Number of pages4
Issue number6018
Publication statusPublished - 11 Feb 2011
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • General

Cite this

Tavani, M., Bulgarelli, A., Vittorini, V., Pellizzoni, A., Striani, E., Caraveo, P., Weisskopf, M. C., Tennant, A., Pucella, G., Trois, A., Costa, E., Evangelista, Y., Pittori, C., Verrecchia, F., Del Monte, E., Campana, R., Pilia, M., De Luca, A., Donnarumma, I., ... Bignami, G. F. (2011). Discovery of powerful gamma-ray flares from the Crab Nebula. Science, 331(6018), 736 - 739.