GCN Circular 17170
Subject
GRB 141212A: extended object within the XRT error circle
Date
2014-12-12T22:18:17Z (10 years ago)
From
Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst <malesani@dark-cosmology.dk>
D. Malesani (DARK/NBI), P. D'Avanzo (INAF/OABr), V. D'Elia (INAF/OAR and
ASI/ASDC), S. D. Vergani (CNRS/GEPI), G. Andreuzzi (INAF/TNG), A. Garcia
de Gurtubai Escudero (INAF/TNG), A. Bonomo (INAF/OATo), report on behalf
of the CIBO collaboration:
We observed the field of GRB 141212A (Ukwatta et al., GCN 17158) using
the TNG optical telescope located in La Palma. Observations started on
2014 Dec 12.832 UT (7.73 hr after the GRB) and consisted of 10x240 s in
the R band. The PSF in our image was around 1.5".
Within the XRT error circle (Osborne et al., GCN 17164; see also
http://www.swift.ac.uk/xrt_positions/), we detect a single, extended
object (A), with coordinates (J2000):
RA = 02:36:29.95
Dec = +18:08:47.2
Its Vega magnitude is R = 22.66 +- 0.23, assuming R = 16.83 for the USNO
star at RA = 02:36:35.95, Dec = +18:09:16.8.
We cannot yet make any claim about variability, so the connection of
this object with GRB 141212A is unclear. This may be the GRB host,
though some contribution from an afterglow cannot be excluded.
We also note the presence of two extended objects just outside the XRT
error circle.
(B): RA = 02:36:30.25, Dec = +18:08:50.1, R = 22.29 +- 0.16;
(C): RA = 02:36:29.64, Dec = +18:08:50.2, R ~ 24.0
Object (C) is barely detected. No other sources are visibile in the
proximity of the XRT error circle down to a limiting magnitude of R = 24.
A finding chart can be seen at the following URL:
http://www.astro.ku.dk/~malesani/GRB/141212A/GRB141212A_TNG.jpg