A Two-component Explosion Model for the Giant Flare and Radio Afterglow
نویسندگان
چکیده
The brightest giant flare from the soft g-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 (∼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 twocomponent 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. Subject headings: gamma rays: bursts — ISM: jets and outflows — stars: individual (SGR 1806 20) Online material: color figures
منابع مشابه
A Two-component Explosion Model for the Giant Flare and Radio Afterglow from Sgr1806-20
The brightest giant flare from the soft γ-ray repeater (SGR) 1806-20 was detected on 2004 December 27. The isotropic-equivalent energy release of this burst is at least one order of magnitude more energetic than those of the two other SGR giant flares. Starting from about one week after the burst, a very bright (∼ 80 mJy), fading radio afterglow was detected. Follow-up observations revealed the...
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