GCN Circular 6130
Subject
GRB 070223: Swift-XRT Refined Analysis
Date
2007-02-23T11:01:49Z (17 years ago)
From
Loredana Vetere at PSU <vetere@astro.psu.edu>
L. Vetere (PSU) reports on behalf of the Swift-XRT team:
We have analysed the first four orbits (up to 16.5 ks after the BAT trigger) of
Swift XRT data for GRB 070223 (Vetere et al., GCN 6126). Using ~2.8 ks of
Photon Counting (PC) mode data we find the following refined position:
RA (J2000) = 10h 13m 48.4s
Dec(J2000) = +43d 07' 58.2"
with an error radius of 4.5 arcseconds (90% confidence). This is 4.4 arcsec away
from XRT initial position and 4.1 arcsec from the possible optical candidate
reported by A. Melandri (GCN 6127).
The WT lightcurve shows a rapid decay with a slope of alpha~2.3 while the PC
light curve shows a possible flattening (~0.6) but we still need more data to
confirm it.
The WT mode spectrum can be fitted with a single power law of photon index of
1.7 +/- 0.1 and column density of (4.5 +/-0.1 )e21 cm**-2. We note the Galactic
column density in the direction of the source is 1.1e20 cm**-2.
The 0.3-10 keV observed flux was 6.5e-10 ergs cm**-2 s**-1, which corresponds to
an unabsorbed flux of 9.2e-10 ergs cm**-2 s**-1.
This circular is an official product of the Swift-XRT team.