A two-component explosion model for the giant flare and radio afterglow from SGR 1806-20

作者：Dai ZG^*; Wu XF; Wang XY; Huang YF; Zhang B

来源：Astrophysical Journal, 2005, 629(2): L81-L84.

DOI：10.1086/449312

• gamma rays : bursts
• ISM : jets and outflows
• stars : individual (SGR 1806-20)

The brightest giant flare from the soft gamma-ray repeater (SGR) 1806 - 20 was detected on 2004 December 27. The isotropic-equivalent energy release of this burst is at least 1 order of magnitude more energetic than those of the two other SGR giant flares. Starting from about 1 week after the burst, a very bright (similar to 80 mJy), fading radio afterglow was detected. Follow-up observations revealed the multifrequency light curves of the afterglow and the temporal evolution of the source size. Here we show that these observations can be understood in a two-component explosion model. In this model, one component is a relativistic collimated outflow responsible for the initial giant flare and the early afterglow, and the other component is a subrelativistic wider outflow responsible for the late afterglow. We also discuss the triggering mechanisms of these two components within the framework of the magnetar model.

• 出版日期2005-8-20
• 单位南京大学