GRB 170519A: Thermal Radiation in an X-ray Flare and Decaying Magnetic Fields for the Early-Time Afterglow

Zi-Min Zhou, Liang-Jun Chen, Rui-Quan Li +5

GRB 170519A was discovered by \emph{Swift}/BAT, and then observed by \emph{Swift}/XRT, \emph{Swift}/UVOT, and ground-based telescopes. We report Lick/KAIT observations of GRB 17051…