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GCN Circular 2068

GRB 030329: Observations with ANDICAM
2003-04-02T01:47:33Z (21 years ago)
Josh Bloom at Harvard/CFA <>
GRB 030329: Observations with ANDICAM

J. S. Bloom (CfA), M. Buxton (Yale), C. Bailyn (Yale), P. G. Van
Dokkum (Yale), S. R. Kulkarni (Caltech) report:

"We observed the afterglow of GRB 030329 (GCN #1985, GCN #1997), using
CTIO 1.3m + ANDICAM on 2003 April 1.15 UT in photometric conditions. The
OT was well detected in BVIJH at the following brightness levels:

                                              UT Start, Int Time
B = 17.671 +/- 0.031   tgrb - t = 2.6676 day (03:33:29, 600 sec)
V = 17.263 +/- 0.043   tgrb - t = 2.6761 day (03:45:52, 600 sec)
I = 16.482 +/- 0.056   tgrb - t = 2.6870 day (04:01:30, 600 sec)

Optical photometry was calibrated to the Henden secondary standards (GCN
#2023). Zeropoint systematics dominate the uncertainties. Magnitudes have
not been corrected for Galactic extinction. We intend to obtain an IR
zeropoint and IR secondary standards over the next few nights.

Assuming a negligible change in flux between observations, we find (V - I)
= 0.781 +/- 0.070, confirming the V-I color reported in Li et al. (GCN
#2064). We find (B - V) = 0.408 +/- 0.053, which is inconsistent with Li
et al, but consistent with the B-V color reported Fitzgerald & Orosz (GCN

A color composite image of the field may be viewed at:

More information about ANDICAM can be obtained at:

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