TITLE:   GCN CIRCULAR
NUMBER:  10911
SUBJECT: GRB 100628A: Second epoch of Magellan near-IR observations
DATE:    10/06/30 03:09:37 GMT
FROM:    Edo Berger at Harvard  <eberger@cfa.harvard.edu>

E. Berger (Harvard), T. Guver (U. of Arizona), W. Fong, R. Chornock
(Harvard) report:

"We re-observed the location of the potential X-ray afterglow (GCNs
18099, 10907) of the short GRB 100628A (GCN 10895) with the PANIC
infrared imager on the Magellan/Baade 6.5-m telescope on 2010 June
29.98 UT (39.2 hours after the burst and 21.8 hours after our previous
observation: GCN 10902).  A total of 27 min on source were obtained in
the J-band with seeing of about 0.5 arcsec.  Digital image subtraction
of the two epochs does not reveal any variable sources within the XRT
error circle or in coincidence with the galaxy "G1" to a 5-sigma limit
of J=21.6 mag at 17.2 hours after the burst.  This result supports the 
conclusions of Levan et al. (GCN 10909)."