# Optical Flash of GRB 990123: Constraints on the Physical Parameters of the Reverse Shock

@article{Fan2002OpticalFO,
title={Optical Flash of GRB 990123: Constraints on the Physical Parameters of the Reverse Shock},
author={Y. Z. Fan and Z. G. Dai and Y. F. Huang and Tan Lu},
journal={Chinese Journal of Astronomy and Astrophysics},
year={2002},
volume={2},
pages={449-453}
}
• Y. Fan, +1 author T. Lu
• Published 1 October 2002
• Physics
• Chinese Journal of Astronomy and Astrophysics
The optical flash accompanying GRB 990123 is believed to be powered by the reverse shock of a thin shell. With the best-fit physical parameters for GRB 990123 and the assumption that the parameters in the optical flash are the same as in the afterglow, we show that: 1) the shell is thick rather than thin, and we have provided the light curve for the thick shell case which coincides with the observation; 2) the theoretical peak flux of the optical flash accounts for only 3◊10 4 of the observed…
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