Abstract
SGR 1806-20 has been observed for more than 2 years with the INTEGRAL satellite. In this period the source went from a quiescent state into a very active one culminating in a giant flare on December 27, 2004. Here we report on the properties of all the short bursts detected with INTEGRAL before the giant flare. We derive their number-intensity distribution and confirm the hardness-intensity correlation for the bursts found by Gotz et al. (2004a, A&A, 417, L45). Our sample includes a very bright outburst that occurred on October 5, 2004, during which over one hundred bursts were emitted in 10 minutes, involving an energy release of 3 x 1042 erg. We present a detailed analysis of it and discuss our results in the framework of the magnetar model.
Original language | English |
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Journal | Astronomy and Astrophysics |
Volume | 445 |
Issue number | 1 |
Pages (from-to) | 313-321 |
ISSN | 0004-6361 |
Publication status | Published - 2006 |
Keywords
- gamma rays : bursts
- stars : pulsars : general
- stars : pulsars : individual : SGR 1806-20
- gamma rays : observations