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GCN Circular 1365

Subject

GRB 020409: No Evidence for an Optical Afterglow

Date

2002-04-12T21:36:27Z (23 years ago)

From

Stephen Holland at U. of Notre Dame <sholland@nd.edu>

S. T. Holland, P. M. Garnavich (Notre Dame), J. A. Munoz (IAC),
   K. Z. Stanek (Harvard-Smithsonian CfA), K. Augustesen,
   B. L. Jensen, J. Hjorth (Copenhagen), J. Gorosabel (IAA, Granada),
   and M. Giavalisco (STScI) report:

     We have obtained additional R-band images of the error box of
GRB 020409 (Piro 2002, GCN 1347Loading...
 
 ) using the 4Shooter on the 1.2-meter
telescope at the Fred Lawrence Whipple Observatory (FLWO).  The first
images were taken on 2002 April 11 at 03:50 UT and had a total
exposure time of 1020 seconds.  The second set of images was taken on
April 12 at 03:55 and had a total exposure time of 1200 seconds.
These data were combined to form two deep images of the field which
were subtracted from each other using the methods described in
Schmidt et al. (1998, ApJ, 507, 46).  We find no evidence for
variability greater than 0.1 mag in 24 hours in any object in the
BeppoSAX error box down to a limiting magnitude of approximately R =
21.5.

     To obtain a longer time baseline (31.5 hours) we compared the
FLWO images to the combined exposures taken on April 11 at the
Brorfelde Observatory (Holland et al. 2002, GCN 1359Loading...
 
 ).  Again, we
found no evidence for an optical afterglow.

     Images are available at
<http://www.nd.edu/~sholland/grb/grb020409/index.html>.

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