[vsnet-grb-info 3321] GRB060512: Late-Time P200 Observations

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  5156
SUBJECT: GRB060512: Late-Time P200 Observations
DATE:    06/05/23 04:50:32 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko at srl.caltech.edu>

S. B. Cenko and W. H. Baumgartner (Caltech) report on behalf of a larger
collaboration:

We have imaged the field of GRB060512 (Cummings et al.; GCN 5117) with the
Large Format Camera mounted on the 5-m Palomar Hale Telescope.
Observations consisted of 5 x 180 s images in the r' filter taken at a
mean epoch of May 21.25 UT.  At the location of the optical afterglow, we
detect an object with approximate r' magnitude 23.7 +/- 0.2 (calculated
with respect the SDSS calibration provided by Cool et al.; GCN 5120).

If we assume limited contamination from an underlying host galaxy, the
afterglow decay remains consistent with the early-time power-law index of
0.85 (Klotz et al.; GCN 5140), indicating a late jet-break time.  However,
futher observations are required to verify the host galaxy brightness.