[vsnet-grb-info 9908] GRB 101023A: Gemini discovery of optical afterglow

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  11366
SUBJECT: GRB 101023A: Gemini discovery of optical afterglow
DATE:    10/10/24 03:00:08 GMT
FROM:    Andrew Levan at U.of Leicester  <A.J.Levan at warwick.ac.uk>

A.J.Levan (U. Warwick), D. Perley (U. Berkeley) and P. D'Avanzo
(INAF-OAB)  report for a larger collaboration:

"We observed the field of GRB 101023A (Saxton et al. GCN 11363)
with GMOS on Gemini-South. We obtained a first epoch of observations
in the r-band beginning at 24 October 00:38, approximately 1.8 hours
post-burst. A second epoch was obtained at 01:26. In these two
observations we identify a fading point source at a location of

RA(J2000) 21:11:51.24 
DEC(J2000) -65:23:15.84

We identify this as the afterglow of GRB 101023A. The afterglow
fades by approximately 0.35 magnitudes between the two epochs of
observation, and has r~20.5 in our first epoch (based on archival
zeropoints). The afterglow position is ~2.8" from the refined XRT 
position of Osborne et al. (GCN 11365).

We thank the staff of Gemini, in particular Henry Lee, for their
help with these observations."