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A Unified Model of Short and Long Gamma-Ray Bursts, X-Ray Rich Gamma-Ray Bursts, and X-Ray Flashes

Ryo Yamazaki·Kunihito Ioka·Takashi Nakamura
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Abstract

Taking into account the recent suggestion that a short gamma-ray burst (GRB) looks like the first 1 sec of a long GRB, we propose that the jet of a GRB consists of multiple sub-jets or sub-shells (i.e., an inhomogeneous jet model). The multiplicity of the sub-jets along a line of sight n_s is an important parameter. If n_s is large (>> 1) the event looks like a long GRB, while if n_s is small (~1) the event looks like a short GRB. If our line of sight is off-axis to any sub-jets, the event looks like an X-ray flash or an X-ray rich GRB. The log-normal distribution of durations of short and long GRBs are also suggested in the same model.

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Ryo Yamazaki, Kunihito Ioka, Takashi Nakamura. 2004-05-12. A Unified Model of Short and Long Gamma-Ray Bursts, X-Ray Rich Gamma-Ray Bursts, and X-Ray Flashes. https://doi.org/10.1086/421872

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