Cosmological X-Ray Flashes from Off-Axis Jets
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چکیده
The 〈V/Vmax〉 of the cosmological X-ray flashes detected by WFC/BeppoSAX is calculated 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, off-axis emission from sources at z≤4 can be seen. The theoretical 〈V/Vmax〉 is less than 0.4, which is consistent with the observational result of 0.27±0.16 at the 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.
منابع مشابه
Cosmological X-ray Flashes in the Off-Axis Jet Model
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...
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تاریخ انتشار 2003