Cosmological X-ray Flashes in the Off-Axis Jet Model

نویسندگان

  • Ryo Yamazaki
  • Takashi Nakamura
چکیده

The 〈V/Vmax〉 of the cosmological X-ray flashes detected by Wide Field Cameras on BeppoSAX is calculted theoretically in a simple jet model. The total emission energy from the jet is assumed to be constant. We find that if the jet opening half-angle is smaller than 0.03 radian, the theoretical 〈V/Vmax〉 is less than ∼ 0.4, which is consistent with the recently reported observational value of 0.27 ± 0.16 in 1 σ level. This suggests that the off-axis GRB jet with the small opening half-angle at the cosmological distance can be identified as the cosmological X-ray flash. Subject headings: gamma rays: bursts —gamma rays: theory

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تاریخ انتشار 2002