[vsnet-grb-info 4508] GRB 070412: Gemini/GMOS afterglow candidate

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  6280
SUBJECT: GRB 070412: Gemini/GMOS afterglow candidate
DATE:    07/04/12 07:23:34 GMT
FROM:    Edo Berger at Carnegie Obs  <eberger at ociw.edu>

E. Begrer (Carnegie) reports on behalf of a larger collaboration:

"We observed the XRT error circle of GRB 070412 (GCN 6273) with GMOS on 
the Gemini-north telescope for a total of 360 sec in i-band starting on 
2007 Apr 12.229 UT (4 hr after the burst).  Within the XRT error circle we 
find a single faint object with i=23.9+/-0.2 mag (using the zeropoint on 
the GMOS website) located at:

 	RA = 12:06:10.585
 	DEC = +40:08:24.83  (J2000)

with an uncertainty of about 0.2".  This position is 3.2" away from the 
center of the XRT error circle (GCN 6273) and 2.1" away from the I-band 
source discussed in GCN 6279.  The non-detection of an object at this 
position in the R-band to a limit of 24 mag at t=1 hr (GCN 6276) indicates 
that this object (if it is the afterglow) is red, with R-I ~ 1.6 mag for a 
fading rate of t^-1."