GCN Circular 15173
Subject
GRB 130903A: Swift-XRT observations
Date
2013-09-03T20:11:17Z (11 years ago)
From
Dirk Grupe at PSU/Swift-XRT <dxg35@psu.edu>
Dirk Grupe (PSU) and Stephen Holland (STSCI) report on behalf of the
Swift team:
We have analysed 3.2 ks of XRT data for the INTEGRAL-detected burst:
GRB 130903A, from 39.6 ks to 46.4 ks after the INTEGRAL trigger. The
data are entirely in Photon Counting (PC) mode. An X-ray source is
detected within the INTEGRAL error circle (Mereghetti et al., GCN circ.
15169). Using 1789 s of PC mode data and 1 UVOT images, we find an
enhanced XRT position (using the XRT-UVOT alignment and matching UVOT
field sources to the USNO-B1 catalogue): RA, Dec = 82.13013, -0.12667
which is equivalent to:
RA (J2000): 05h 28m 31.23s
Dec(J2000): -00d 07' 36.0"
with an uncertainty of 4.3 arcsec (radius, 90% confidence). This
position is 12 arcsec from the INTEGRAL position. Currently the source
has a 0.3-10 keV count rate in the Swift XRT of (4.9+4.9-3.0)e-3
counts/s.
We cannot determine at the present time whether the source is fading.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020294.
The Swift UVOT observed the field of GRB 130903A in V and U for 2462
and 780s, respectively. No optical counterpart was found. The 3-sigma
upper limits at the position of the X-ray source are 20.6 in V and 20.4
in U.
This circular is an official product of the Swift team.