GCN Circular 210
Subject
GRB990123 optical observations
Date
1999-01-24T15:35:49Z (25 years ago)
From
Paul Vreeswijk at U of Amsterdam <pmv@astro.uva.nl>
Eran Ofek and Elia M. Leibowitz, Wise Observatory, Tel Aviv University
report:
>From 4 CCD frames of the object taken at the WO between Jan
24.0617-24.1162 we have determined an average R magnitude of
19.87+-0.2, with calibration based on 4 USNO A2.0 stars. The decay
parameter in the R band over that time interval is -1.9+-0.1. On Jan
24.0625, the color index of the object was B-R=-0.48+-0.25.
This report may be cited.