GCN Circular 1885
Subject
GRB 030226, optical observations
Date
2003-02-26T19:17:15Z (21 years ago)
From
Peter Garnavich at U of Notre Dame <pgarnavi@miranda.phys.nd.edu>
P. Garnavich (Notre Dame), K. von Braun (DTM), K. Stanek (CfA)
We have calibrated the R-band images of the GRB 030226 field
(Fox et al. GCN 1879; von Braun et al. GCN 1881) taken
with the 1-m Swope telescope on Feb. 26 (UT). The Landolt
standard field PG1323-086 (Landolt 1992, AJ, 104, 340) was
observed at the end of the photometric night. We estimate the
following magnitudes for stars near the optical afterglow:
Star A 11:33:03.214 +25:51:30.73 (2000) R=15.39 +/-0.05
Star B 11:32:59.808 +25:52:38.73 (2000) R=17.06 +/-0.05
where most of the error is due to the uncertain airmass correction.
Star A was noted in GCN 1881 as having a USNO magnitude of 15.0.
Using this calibration we find the following brightness for
the afterglow from the Swope data:
Feb. 26.305 (3.5 hours after the burst) R=18.44 +/-0.05
The images show only a 0.02 mag variation in the
brightness of the afterglow over a 20 minutes span.
A finder chart for the afterglow and calibrated stars
can be found at: http://www.nd.edu/~pgarnavi/grb030226.jpg
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