1999A&AS..138..437N

Over a total of 20 gamma-ray bursts localized with arcmin accuracies, GRB 980519 represents the 13^th detected by the BeppoSAX Wide Field Cameras (WFCs). An X-ray TOO observation performed by the BeppoSAX Narrow Field Instruments (NFIs), starting about 9.5 hours after the high energy event, revealed X-ray afterglow emission in the 0.1-10 keV energy range. The flux decay was particularly fast with a power-law index of ≃1.8. This is the fastest decay so far measured. Signs of bursting activity are evident. The power-law spectral index of 2.8^+0.6_–0.5 is quite soft but not unique among GRB afterglows. VR_cI_c optical emission was detected as soon as 8 hours after the GRB and the power-law flux decay in all these bands were all consistent with δ≃2.0. As for the X-ray, this is the fastest of all the 9 optically identified afterglows but GRB 980326. A candidate host galaxy with magnitude R_c=26 has been reported and variable radio emission detected.