[vsnet-grb-info 9027] GRB 100316D: GROND Detection of the Optical/NIR Afterglow Candidate

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  10514
SUBJECT: GRB 100316D: GROND Detection of the Optical/NIR Afterglow Candidate
DATE:    10/03/17 04:47:13 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike at clemson.edu>

Paulo Afonso (MPE Garching), Adria Updike (Clemson University), Marco
Nardini, Robert Filgas, Abdullah Yoldas, and Jochen Greiner (MPE Garching)
report on behalf of the GROND team:

We observed the field of GRB 100316D (Swift trigger 416135; Stamatikos et
al., GCN 10496) simultaneously in g'r'i'z'JHK with GROND (Greiner et al.
2008, PASP 120, 405) mounted at the 2.2 m ESO/MPI telescope at La Silla
Observatory (Chile).

Observations started at 00:28 UT on March 17, 11.66 hours after the GRB
trigger, and are continuing. They were performed at an average seeing of
1" and at an average airmass of 1.1.

We detect what appears to be a bright point on the edge of the extended
object noted by Sakamoto et al. (GCN 10511) within the XRT error circle. 
This is consistent with the source identified by Vergani et al. (GCN
10512).  The source is detected in all bands, suggesting a redshift < 3.5.
 We cannot yet determine if this source is related to the GRB.

Further observations are required to establish variability, and to check
whether the optical bands show similarities to GRB 060218 - SN 2006aj as
reported by Sakamoto et al. (GCN 10511) for the gamma ray and x-ray bands.