GCN Circular 7310
Subject
GRB 080212: REM refined analysis
Date
2008-02-13T18:12:44Z (16 years ago)
From
Paolo D'Avanzo at INAF-OAB <paolo.davanzo@brera.inaf.it>
P. D'Avanzo, L.A. Antonelli, S. Covino, D. Fugazza, L. Calzoletti, S.
Campana, G. Chincarini, M.L. Conciatore, S. Cutini, V. D'Elia, F.
D'Alessio, F. Fiore, P. Goldoni, D. Guetta, C. Guidorzi, G.L. Israel,
E. Maiorano, D. Malesani, N. Masetti, A. Melandri, E.J.A. Meurs, L.
Nicastro, E. Palazzi, E. Pian, S. Piranomonte, L. Stella, G. Stratta,
G. Tagliaferri, G. Tosti, V. Testa, S.D. Vergani, F. Vitali report on
behalf of the REM team:
We performed a more careful analysis of the REM H-band images of GRB
080212 (Ziaeepour et al. GCN 7296). We confirm the afterglow detection
reported in D'Avanzo et al. (GCN 7302).The observations have been
carried out on Feb 13.2063 UT (about 11.4 hours after the burst) and
consist of three sets of images (lasting 10, 30 and 60 s respectively).
We confirm the presence of a H = 15.3 � 0.2 object (calibrated against
the 2MASS catalogue) about 2.5" East of the K-type star (Berger, GCNs
7294 & 7304). The object is visible in both the 30 s and 60 s images at
the following coordinates (J2000):
R.A. = 15:24:35.42
Dec. = -22:44:28.8
with an uncertainty of 0.3" (the REM pixel size is 1.2"/pixel) .
When compared to the GROND optical detection (obtained about 1.7 hours
later, Kuepcue Yoldas et al. GCN 7303), our H-band measurement implies
a colour I-H ~ 7 mag, which is very red. A possible way out is to invoke
remarkable flaring activity around the time of the REM observation. We
note that the X-ray light curve (available at:
http://www.swift.ac.uk/xrt_curves/00303105/) shows some evidence for
rebrightening about 2 hr before the REM observation.
A finding chart, showing the detection at different H-band images can be
found at the following URL:
http://www.brera.inaf.it/utenti/davanzo/public/grb/GRB080212/GRB080212_REMIR_FC.jpg
