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arXiv · 0912.2921

Detection of Gamma-Ray Emission from the Vela Pulsar Wind Nebula with AGILE

A. Pellizzoni·A. Trois·M. Tavani·M. Pilia·A. Giuliani·G. Pucella·P. Esposito·S. Sabatini·G. Piano·A. Argan·G. Barbiellini·A. Bulgarelli·M. Burgay·P. Caraveo·P. W. Cattaneo·A. W. Chen·V. Cocco·T. Contessi·E. Costa·F. D'Ammando·E. Del Monte·G. De Paris·G. Di Cocco·G. Di Persio·I. Donnarumma·Y. Evangelista·M. Feroci·A. Ferrari·M. Fiorini·F. Fuschino·M. Galli·F. Gianotti·A. Hotan·C. Labanti·I. Lapshov·F. Lazzarotto·P. Lipari·F. Longo·M. Marisaldi·M. Mastropietro·S. Mereghetti·E. Moretti·A. Morselli·L. Pacciani·J. Palfreyman·F. Perotti·P. Picozza·C. Pittori·A. Possenti·M. Prest·M. Rapisarda·A. Rappoldi·E. Rossi·A. Rubini·P. Santolamazza·E. Scalise·P. Soffitta·E. Striani·M. Trifoglio·E. Vallazza·S. Vercellone·F. Verrecchia·V. Vittorini·A. Zambra·D. Zanello·P. Giommi·S. Colafrancesco·A. Antonelli·L. Salotti·N. D'Amico·G. F. Bignami
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Abstract

Pulsars are known to power winds of relativistic particles that can produce bright nebulae by interacting with the surrounding medium. These pulsar wind nebulae (PWNe) are observed in the radio, optical, x-rays and, in some cases, also at TeV energies, but the lack of information in the gamma-ray band prevents from drawing a comprehensive multiwavelength picture of their phenomenology and emission mechanisms. Using data from the AGILE satellite, we detected the Vela pulsar wind nebula in the energy range from 100 MeV to 3 GeV. This result constrains the particle population responsible for the GeV emission, probing multivavelength PWN models, and establishes a class of gamma-ray emitters that could account for a fraction of the unidentified Galactic gamma-ray sources.

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A. Pellizzoni, A. Trois, M. Tavani, M. Pilia, A. Giuliani, G. Pucella, P. Esposito, S. Sabatini, G. Piano, A. Argan, G. Barbiellini, A. Bulgarelli, M. Burgay, P. Caraveo, P. W. Cattaneo, A. W. Chen, V. Cocco, T. Contessi, E. Costa, F. D'Ammando, E. Del Monte, G. De Paris, G. Di Cocco, G. Di Persio, I. Donnarumma, Y. Evangelista, M. Feroci, A. Ferrari, M. Fiorini, F. Fuschino, M. Galli, F. Gianotti, A. Hotan, C. Labanti, I. Lapshov, F. Lazzarotto, P. Lipari, F. Longo, M. Marisaldi, M. Mastropietro, S. Mereghetti, E. Moretti, A. Morselli, L. Pacciani, J. Palfreyman, F. Perotti, P. Picozza, C. Pittori, A. Possenti, M. Prest, M. Rapisarda, A. Rappoldi, E. Rossi, A. Rubini, P. Santolamazza, E. Scalise, P. Soffitta, E. Striani, M. Trifoglio, E. Vallazza, S. Vercellone, F. Verrecchia, V. Vittorini, A. Zambra, D. Zanello, P. Giommi, S. Colafrancesco, A. Antonelli, L. Salotti, N. D'Amico, G. F. Bignami. 2010-01-01. Detection of Gamma-Ray Emission from the Vela Pulsar Wind Nebula with AGILE. https://doi.org/10.1126/science.1183844

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