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GCN Circular 1333

GRB 020405: Decay index
2002-04-07T02:46:33Z (22 years ago)
Paul Price at RSAA, ANU at CIT <>
P.A. Price, B.P. Schmidt (RSAA, ANU) and T.S. Axelrod (Arizona)

We have re-observed the afterglow candidate (GCN #1326) with the
robotic MSO 50-inch telescope + MACHO imager at 2002 Apr 6.43.
The afterglow candidate has faded by approximately 1 magnitude
since the observations of Apr 5.75 (GCN #1326), from which we
derive an optical decay index of alpha ~ 1.26.  Using the reference
star of Hjorth et al. (GCN #1329), we find that R ~ 19.9 mag at
Apr 6.43.  This value does not appear to be consistent with that of
Hjorth et al., which might be explained by the filter mis-match
and use of different apertures.

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