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GCN Circular 3907

GRB 050824: MDM Observations
2005-09-02T18:31:11Z (19 years ago)
Jules Halpern at Columbia U. <>
J. P. Halpern (Columbia U.) and N. Mirabal (U. Michigan) report on behalf of
the MDM Observatory GRB follow-up team:

"We observed the Swift GRB 050824 afterglow (Gorosabel et al., GCN #3865)
in the R band on five consecutive nights using the MDM 1.3m telescope.
Photometry was established using two Landolt standard-star fields on one
photometric night.  From 5.6 to 12.6 hours, the decay is consistent with
a power law of index -0.55+/-0.05, which extrapolates well to the MASTER 
photometry at 24 and 47 minutes (Lipunov et al., GCN #3883).  This decay 
index is similar to that seen in the Swift XRT light curve, -0.4+/-0.2
(Campana et al., CGN #3877), immediately preceding the MDM observations.
An unobserved inflection in the optical light curve then occurs, and from
1.3 to 4.4 days the decay index is -0.43+/-0.04.  Our final measured point 
is R=22.18+/-0.06 on Aug. 29.32.

Images and light curves are posted at

This message may be cited."
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