Publication Date:
2009
abstract:
We present the results of extensive observations by the gamma-ray AGILE satellite of the Galactic region hosting the Carina nebula and the remarkable colliding wind binary Eta Carinae (eta Car) during the period 2007 July-2009 January. We detect a gamma-ray source (1AGL J1043-5931) consistent with the position of eta Car. If 1AGL J1043-5931 is associated with the Car system, our data provide the long sought first detection above 100 MeV of a colliding wind binary. The average gamma-ray flux above 100 MeV and integrated over the preperiastron period 2007 July-2008 October is F(gamma) = (37 +/- 5) x 10(-8) ph cm(-2) s(-1) corresponding to an average gamma-ray luminosity of L(gamma) = 3.4 x 10(34) erg s(-1) for a distance of 2.3 kpc. We also report a two-day gamma-ray flaring episode of 1AGL J1043-5931 on 2008 October 11-13 possibly related to a transient acceleration and radiation episode of the strongly variable shock in the system.
Iris type:
Articolo su Rivista
Keywords:
Agile; Galactic region; Carina Nebula; wind binary Eta Carinae
List of contributors:
Tavani, Marco; Sabatini, Sabina; Pian, Elena; Bulgarelli, A; Caraveo, Patrizia; Viotti, Rf; Corcoran, Mf; Giuliani, Andrea; Pittori, Carlotta; Verrecchia, F; Vercellone, S; Mereghetti, S; Argan, A; Barbiellini Amidei, Guido; Boffelli, Fabrizio; Cattaneo Paolo, Walter; Chen, Rongchang; Cocco, Veronica; D'Ammando, F; Costa, E; De Paris, G; Del Monte, Ettore; Di Cocco, G; Donnarumma, I; Evangelista, Yuri; Ferrari, Attilio; Feroci, Marco; Fiorini, Massimiliano; Froysland Tom, Vidar; Fuschino, F; Galli, M; Gianotti, F; Labanti, C; Lapshov, I; Lazzarotto, F; Lipari, Paolo; Longo, Francesco; Marisaldi, M; Mastropietro, M; Morelli, Ennio; Moretti, Elena; Morselli, Aldo; Pacciani, Luigi; Pellizzoni, A; Perotti, F; Piano, Giovanni; Picozza, Piergiorgio; Pilia, Maura; Porrovecchio, G; Pucella, Gianluca; Prest, Michela; Rapisarda, Massimo; Rappoldi, Andrea; Rubini, Alda; Soffitta, P; Trifoglio, M; Trois, A; Vallazza Erik, Silvio; Vittorini, Valerio; Zambra, A; Zanello, Dino; Santolamazza, P; Giommi, P; Colafrancesco, Sergio; Antonelli Lucio, Angelo; Salotti, L.
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