GCN Circular 1993
Subject
GRB 030328 Optical Observations
Date
2003-03-29T17:03:41Z (22 years ago)
From
Jens Hjorth at U.Copenhagen <jens@astro.ku.dk>
M. I. Andersen (Astrophysikalisches Institut Potsdam),
G. Masi (University of Rome "Tor Vergata" and ESO, Chile),
B. L. Jensen and J. Hjorth (University of Copenhagen) report:
We have obtained R-band observations of the optical afterglow of
GRB 030328 (Peterson & Price, GCN 1974), using the Danish 1.54m
telescope (La Silla) + DFOSC. Using the zero point reported by
Fugazza et al. (GCN 1982) (R = 16.31 for star B) a preliminary
analysis gives
Mar. 29, 02:59 UT 20.91 +/- 0.09
Mar. 29, 03:12 UT 20.73 +/- 0.07
Mar. 29, 03:34 UT 21.00 +/- 0.09
Mar. 29, 03:54 UT 20.85 +/- 0.06
Mar. 29, 04:15 UT 21.00 +/- 0.07
Mar. 29, 04:42 UT 20.95 +/- 0.07
Mar. 29, 05:21 UT 21.10 +/- 0.07
Mar. 29, 05:53 UT 21.03 +/- 0.07
Mar. 29, 07:17 UT 21.23 +/- 0.10
Mar. 29, 07:46 UT 21.36 +/- 0.11
A fit to this data set gives a decay index of alpha = 1.6 +/- 0.3. If
the two last data points are ignored and the two data points of Fugazza
et al. are included, a decay index of alpha = 1.2 +/- 0.2 is derived,
consistent with the early decay index of alpha = 1.0 +/- 0.1 reported
by Price & Peterson (GCN 1977). This may indicate that the light curve
steepened around t = 0.8 days.