TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  5253
SUBJECT: GRB 060604, optical observations
DATE:    06/06/14 18:24:55 GMT
FROM:    Peter Garnavich at U of Notre Dame  <pgarnavi@nd.edu>

Peter Garnavich and Agata Karska (Notre Dame)

We observed the position of GRB 060604 (Page et al., GCN 5212)
with the Vatican Advanced Technology Telescope and 2KCCD
camera on 2006 June 5.45 UT (16.5 hours after the burst).
Six R-band images, each with an exposure time of 120s, were
combined and a source detected at the Swift/UVOT position.

Using an average of five USNO-B1.0 stars (magR2) to set the
zero-point we estimate the brightness of the afterglow at
R=21.6 +/- 0.2 mag. This is only slightly fainter than
the observation by Tanvir et al. (GCN 5216) six hours earlier
and suggests a slow decay or contamination from the host
galaxy.


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