GCN Circular 2171
Subject
GRB030329, SPM optical observations
Date
2003-04-25T11:53:46Z (22 years ago)
From
Sergej Zharikov at OAN IA UNAM <zhar@astrosen.unam.mx>
S. Zharikov, G. Tovmassian, M. Richer (OAN SPM IA UNAM, Ensenada, Mexico)
report:
We have observed the OT GRB030329 found by B.Peterson and P.Price (GCN
1985) using 1.5m telescope of OAN-SPM Observatory, BC, Mexico.
A set of exposures in UBVRI Bessel filters was obtained
24 April and 25 April under photometric and good seeing conditions.
Standard stars RU 149 from Landolt's catalogue
were used for photometric calibrations in the each night.
The results of photometry of summed images are following:
24 April
<Tobs> Texp. Filter Mag.
UT 5:50 5400sec U 21.76(12)
UT 6:56 4800sec B 21.51(6)
UT 5:54 2400sec V 20.73(4)
UT 6:30 3300sec R 20.17(5)
UT 6:10 2400sec I 19.90(5)
Corresponding color indexes are
U-B = 0.25(14) B-V = 0.78(7)
V-R = 0.56(6) R-I = 0.27(6)
25 April
<Tobs> Texp Filter Mag.
UT 5:10 5400sec B 21.63(5)
UT 7:30 3600sec V 21.72(4)
UT 6:17 2400sec R 20.16(5)
UT 8:00 3600sec I 20.01(5)
The magnitudes no changed during those nights.
The OT source looks like a point-like object.
Two faint extended objects detected nearly OT position.
O1: 10:44:50.03 J2000 +21:31:10 R~22.5 distance from OT is about 7"
O2: 10:44:49.4 J2000 +21:31:14 R~22.9 distance from OT is about 9"
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