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Giant flare of SGR 1806-20 from a relativistic jet

Ryo Yamazaki·Kunihito Ioka·Fumio Takahara·Noriaki Shibazaki
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Abstract

Japanese magnetospheric explorer GEOTAIL recorded a detailed light curve during the initial 600 msec of a giant flare from SGR 1806-20 on December 27, 2004. We show that the observed light curve is well explained by an emission from relativistically expanding fireballs, like those of gamma-ray bursts (GRBs). Especially, the observed rapid fading after 500msec suggests that ejecta is collimated in a jet. We derive an upper limit on the jet opening half-angle of 0.2 radian that is as narrow as those of GRBs.

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Ryo Yamazaki, Kunihito Ioka, Fumio Takahara, Noriaki Shibazaki. 2005-04-22. Giant flare of SGR 1806-20 from a relativistic jet. https://doi.org/10.1093/pasj%2F57.3.l11

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