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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·Kenji Toma
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Abstract

We propose a possible unified model of short and long gamma-ray bursts (GRBs), X-ray rich GRBs, and X-ray flashes. The jet of a GRB is assumed to consist 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=1, the event looks like a short GRB. Finally, when n_s=0, the event looks like an X-ray flash or an X-ray rich GRB. Furthermore, our model may also explain the bimodal distributions of T_{90} duration of BATSE-GRBs.

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Ryo Yamazaki, Kunihito Ioka, Takashi Nakamura, Kenji Toma. 2004-10-29. A Unified Model of Short and Long Gamma-Ray Bursts, X-Ray Rich Gamma-Ray Bursts, and X-Ray Flashes. https://doi.org/10.1393/ncc%2Fi2005-10084-6

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