GCN Circular 4338
Subject
GRB 051211B: Swift XRT confirmation of the afterglow
Event
Date
2005-12-12T13:51:50Z (20 years ago)
From
David Burrows at PSU/Swift <dxb15@psu.edu>
V. La Parola, V. Mangano (INAF-IASF), C. Pagani (INAF-OAB), and D. N.
Burrows (PSU), report on behalf of the Swift XRT team:
The Swift XRT began observing GRB 051211B, detected by INTEGRAL (Mereghetti
et al., GCN 4327), at 01:05:28 UT on 12 December 2005 (10.8 ks after the
burst). With five orbits of data (from 11 ks to 36 ks after the burst),
the uncataloged X-ray source reported in Pagani et al. (GCN 4332) is
clearly fading, consistent with being the afterglow of this burst. Our
updated position is
RA 23:2:41.76, Dec 55:04:51.9 (345.6740, 55.0811),
which is 29".8 from the INTEGRAL position and 62".9 from the position of
the candidate optical afterglow reported in GCN 4328 (Klotz et al.). The
lightcurve is initially flat, with a steep power law decay commencing about
20 ks after the burst. Observations are continuing. Refined analysis,
including decay indices and spectral results, will be issued in a further
circular after accumulation of several more orbits of data.