GCN Circular 4332
Subject
GRB 051211B: Swift XRT Observations
Date
2005-12-12T04:46:11Z (18 years ago)
From
David Burrows at PSU/Swift <dxb15@psu.edu>
C. Pagani (INAF-OAB), D. N. Burrows (PSU), V. Mangano and V. La Parola
(INAF-IASF) 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). In the first orbit of data (2.4 ks of exposure time), an
uncataloged X-ray source was detected at the following position:
RA,Dec = 345.6762,+55.081 {23:02:42.3, +55:04:51.7} (J2000)
with an uncertainty of 4.5 arcsec radius (90% containment). This position
includes corrections for the XRT boresight. We detected 58 photons from
this source in Photon-Counting mode at a count rate of 0.024 cps,
corresponding to an observed flux of about 1.3x10-12 ergs/cm^2/sec.
The X-ray source is 25 arcsec from the INTEGRAL position (GCN 4327) and 58
arcsec from the candidate optical afterglow reported in GCN 4328. There is
no X-ray source visible at the position of the candidate optical afterglow.
With the data available at this time we cannot determine whether or not
this source is fading. Observations are continuing, and we will report
further results in a later circular.