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Peak Energy-Isotropic Energy Relation in the Off-Axis Gamma-Ray Burst Model

Ryo Yamazaki·Kunihito Ioka·Takashi Nakamura
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Abstract

Using a simple uniform jet model of prompt emissions of gamma-ray bursts (GRBs), we reproduce the observed peak energy--isotropic energy relation. A Monte Carlo simulation shows that the low-isotropic energy part of the relation is dominated by events viewed from off-axis directions, and the number of the off-axis events is about one-third of the on-axis emissions. We also compute the observed event rates of the GRBs, the X-ray-rich GRBs, and the X-ray flashes detected by HETE-2, and we find that they are similar.

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Ryo Yamazaki, Kunihito Ioka, Takashi Nakamura. 2004-05-12. Peak Energy-Isotropic Energy Relation in the Off-Axis Gamma-Ray Burst Model. https://doi.org/10.1086/421084

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