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Off-axis Emission from the Beamed Afterglow of Gamma Ray Bursts and a Possible Interpretation of Slowly Declining X-Ray Afterglow of GRB980425

Takashi Nakamura
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Abstract

A formula for off-axis emissions from the beamed afterglow of GRBs in a synchrotron model is derived. The formula is applied to an inhomogeneous circumstellar matter obeying n proportional to 1/r**2 suggested for SN1998bw/GRB980425. The slow decline rate as well as the X-ray flux similar to the observed values are obtained for appropriate choice of the parameters so that the association of GRB980425 with SN1998bw is further strengthened.

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Takashi Nakamura. 1999-07-16. Off-axis Emission from the Beamed Afterglow of Gamma Ray Bursts and a Possible Interpretation of Slowly Declining X-Ray Afterglow of GRB980425. https://doi.org/10.1086/312235

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