[vsnet-grb-info 2068] GRB 050824: MDM Observations

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  3907
SUBJECT: GRB 050824: MDM Observations
DATE:    05/09/02 18:31:11 GMT
FROM:    Jules Halpern at Columbia U.  <jules at astro.columbia.edu>

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 
http://www.astro.columbia.edu/~jules/grb/050824/

This message may be cited."