We report on the discovery of >= 100 MeV gamma-rays from the binary system PSR B1259-63/LS 2883 using the Large Area Telescope (LAT) on board Fermi. The system comprises a radio pulsar in orbit around a Be star. We report on LAT observations from near apastron to similar to 128 days after the time of periastron, t(p), on 2010 December 15. No gamma-ray emission was detected from this source when it was far from periastron. Faint gamma-ray emission appeared as the pulsar approached periastron. At similar to t(p) + 30 days, the >= 100 MeV gamma-ray flux increased over a period of a few days to a peak flux 20-30 times that seen during the pre-periastron period, but with a softer spectrum. For the following month, it was seen to be variable on daily timescales, but remained at similar to(1-4) x 10(-6) cm(-2) s(-1) before starting to fade at similar to t(p) + 57 days. The total gamma-ray luminosity observed during this period is comparable to the spin-down power of the pulsar. Simultaneous radio and X-ray observations of the source showed no corresponding dramatic changes in radio and X-ray flux between the pre-periastron and post-periastron flares. We discuss possible explanations for the observed gamma-ray-only flaring of the source.
DISCOVERY OF HIGH-ENERGY GAMMA-RAY EMISSION FROM THE BINARY SYSTEM PSR B1259-63/LS 2883 AROUND PERIASTRON WITH FERMI / Abdo AA; Ackermann M; Ajello M; Allafort A; Ballet J; Barbiellini G; Bastieri D; Bechtol K; Bellazzini R; Berenji B; Blandford RD; Bonamente E; Borgland AW; Bregeon J; Brigida M; Bruel P; Buehler R; Buson S; Caliandro GA; Cameron RA; Camilo F; Caraveo PA; Cecchi C; Charles E; Chaty S; Chekhtman A; Chernyakova M; Cheung CC; Chiang J; Ciprini S; Claus R; Cohen-Tanugi J; Cominsky LR; Corbel S; Cutini S; DAmmando F; de Angelis A; den Hartog PR; de Palma F; Dermer CD; Digel SW; Silva EDE; Dormody M; Drell PS; Drlica-Wagner A; Dubois R; Dubus G; Dumora D; Enoto T; Espinoza CM; Favuzzi C; Fegan SJ; Ferrara EC; Focke WB; Fortin P; Fukazawa Y; Funk S; Fusco P; Gargano F; Gasparrini D; Gehrels N; Germani S; Giglietto N; Giommi P; Giordano F; Giroletti M; Glanzman T; Godfrey G; Grenier IA; Grondin MH; Grove JE; Grundstrom E; Guiriec S; Gwon C; Hadasch D; Harding AK; Hayashida M; Hays E; Johannesson G; Johnson AS; Johnson TJ; Johnston S; Kamae T; Katagiri H; Kataoka J; Keith M; Kerr M; Knodlseder J; Kramer M; Kuss M; Lande J; Lee SH; Lemoine-Goumard M; Longo F; Loparco F; Lovellette MN; Lubrano P; Manchester RN; Marelli M; Mazziotta MN; Michelson PF; Mitthumsiri W; Mizuno T; Moiseev AA; Monte C; Monzani ME; Morselli A; Moskalenko IV; Murgia S; Nakamori T; Naumann-Godo M; Neronov A; Nolan PL; Norris JP; Noutsos A; Nuss E; Ohsugi T; Okumura A; Omodei N; Orlando E; Paneque D; Parent D; Pesce-Rollins M; Pierbattista M; Piron F; Porter TA; Possenti A; Raino S; Rando R; Ray PS; Razzano M; Razzaque S; Reimer A; Reimer O; Reposeur T; Ritz S; Sadrozinski HFW; Scargle JD; Sgro C; Shannon R; Siskind EJ; Smith PD; Spandre G; Spinelli P; Strickman MS; Suson DJ; Takahashi H; Tanaka T; Thayer JG; Thayer JB; Thompson DJ; Thorsett SE; Tibaldo L; Tibolla O; Torres DF; Tosti G; Troja E; Uchiyama Y; Usher TL; Vandenbroucke J; Vasileiou V; Vianello G; Vitale V; Waite AP; Wang P; Winer BL; Wolff MT; Wood DL; Wood KS; Yang Z; Ziegler M; Zimmer S. - In: THE ASTROPHYSICAL JOURNAL LETTERS. - ISSN 2041-8205. - STAMPA. - 736:1(2011), pp. L11.11-L11.16. [10.1088/2041-8205/736/1/L11]
DISCOVERY OF HIGH-ENERGY GAMMA-RAY EMISSION FROM THE BINARY SYSTEM PSR B1259-63/LS 2883 AROUND PERIASTRON WITH FERMI
D'AMMANDO, FILIPPO;
2011
Abstract
We report on the discovery of >= 100 MeV gamma-rays from the binary system PSR B1259-63/LS 2883 using the Large Area Telescope (LAT) on board Fermi. The system comprises a radio pulsar in orbit around a Be star. We report on LAT observations from near apastron to similar to 128 days after the time of periastron, t(p), on 2010 December 15. No gamma-ray emission was detected from this source when it was far from periastron. Faint gamma-ray emission appeared as the pulsar approached periastron. At similar to t(p) + 30 days, the >= 100 MeV gamma-ray flux increased over a period of a few days to a peak flux 20-30 times that seen during the pre-periastron period, but with a softer spectrum. For the following month, it was seen to be variable on daily timescales, but remained at similar to(1-4) x 10(-6) cm(-2) s(-1) before starting to fade at similar to t(p) + 57 days. The total gamma-ray luminosity observed during this period is comparable to the spin-down power of the pulsar. Simultaneous radio and X-ray observations of the source showed no corresponding dramatic changes in radio and X-ray flux between the pre-periastron and post-periastron flares. We discuss possible explanations for the observed gamma-ray-only flaring of the source.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
