Edit GCN Circular

See documentation on Circulars moderation for more information on corrections.

The subject line must contain (and should start with) the name of the transient, which must start with one of the

GRB 111210A

Automatically fill event ID from subject

D. A. Kann, S. Klose (TLS Tautenburg), and J. Greiner, (MPE Garching)
report on behalf of the GROND team:

We observed the field of the Swift GRB 111210A (Swift trigger 509419; 
Siegel et al., GCN #12650) simultaneously in g'r'i'z'JHK with GROND 
(Greiner et al. 2008, PASP, 120, 405) mounted at the 2.2 m ESO/MPG 
telescope at La Silla Observatory (Chile). Observations started on 
December 11, 2011, at 08:06 UT, 0.73 days after the GRB trigger, during 
morning twilight and were partially performed only in the NIR. They were 
taken at an average seeing of 1".1 and at an airmass of 2 to 1.5.

At the position of the X-ray afterglow (Goad et al., GCN #12652) as well 
as the optical candidate (Tanvir et al., GCN #12657), we tentatively 
detect a source in the redder filters.

Based on co-added images of 743 s integration time in g'r'i'z' (centered 
0.7396 days after the trigger) and 2160 s in JHK (centered 0.7520 days 
after the trigger), the following magnitudes and limits (3 sigma, AB 
magnitude system) have been derived:

g' > 22.6,
r' > 23.2,
i' = 22.8 +/- 0.4,
z' = 22.4 +/- 0.3,
J =  21.4 +/ 0.3,
H =  21.4 +/- 0.4,
K >  20.5.

Our r'-band upper limit is not deep enough to check fading against the 
Gemini North candidate. If the faint detections actually represents a real 
object, this is likely the host galaxy of this GRB (Tanvir & Malesani, GCN 
12661).

Magnitudes were calibrated against the SDSS catalog in g'r'i'z' and 2MASS
field stars in JHK.

Body text. If this is your first Circular, please review the style guide. References to Circulars, DOIs, arXiv preprints, and transients are automatically shown as links; see

Back