GCN Circular 12570
Subject
GRB 111117A: TNG observations
Date
2011-11-18T11:32:21Z (12 years ago)
From
Andrea Melandri at INAF-OAB <andrea.melandri@brera.inaf.it>
A. Melandri, D. Fugazza, S. Covino (INAF-OAB) and E. Palazzi (INAF-
IASFBo)
on behalf of a larger collaboration report:
We observed the field of GRB 111117A (Mangano et al. GCN 12559) with
the 3.6m TNG equipped with the Dolores camera. A sequence of 6x300s
images were acquired starting on Nov 17.801 UT (i.e. ~7 hours after
the burst event).
No obvious fading object is detected inside the refined XRT error
circle (Melandri et al. GCN 12565), while the extended object
previously reported by Andersen et al. (GCN 12563), Fong et al. (GCN
12566), Cucchiara et al. (GCN 12567) and Schmidl et al. (GCN 12568) is
clearly visible in our coadded image.
Calibrating against a set of USNO-B1 stars of the field we find R =
23.1 +/- 0.2, consistent with the value found by Andersen et al. (GCN
12563). We caution about the possible fading of this object, as
reported by Fong et al. (GCN 12566), because the apparent difference
of magnitude could be related to the different calibration system.
Since this object is extended also in our image and it does not seem
to vary, it is more likely the host galaxy of GRB 111117A.
We thank the TNG staff for their support, in particular Aldo Fiorenzano.