TITLE:   GCN CIRCULAR
NUMBER:  5806
SUBJECT: GRB 061110A: Swift XRT refined analysis
DATE:    06/11/11 00:05:23 GMT
FROM:    Loredana Vetere at PSU  <vetere@astro.psu.edu>

L. Vetere, D. Morris, C. Pagani, J. Racusin, A. Falcone, D. N. Burrows (PSU)
report on behalf of the Swift XRT team:

We have analysed the first 3 orbits of XRT data for GRB 061110A.
A 560s photon counting mode image provides a refined XRT position:

RA(J2000)  =  22 25 09.9
Dec(J2000) =  -02 15 30.7

with an uncertainty of 3.7 arcsec (90% containment). This position is  2.2
arcsec away from the previous XRT position (Falcone et al. GCN 5795), 1.66
arcsec away from the optical afterglow detection by Chen et al. (GCN 5797)
and 1.5 arcsec away from its later confirmation by Zhai et al. (GCN 5798).

The X-ray light curve in PC mode shows a rapid decay with a slope of -2.36
+/-0.22 in all the 1st orbit. While the 2nd and 3rd orbits show flattening.
A power-law fit to the WT spectrum gives a photon index of 3.1 +/- 0.2 and a
column density of (1.6 +/- 0.2)e21 cm^-2. We note that the galactic hydrogen
column density in the direction of the burst is 4.94e20 cm^-2. The 0.2-10.0 keV
observed mean flux during WT observation is 1.1-09 ergs cm^-2 s^-1, which
corresponds to an unabsorbed flux of ergs 3.4e-09cm^-2 s^-1.

We are waiting for new data to make a prediction of the count rate. Note that
the new event, GRB 061110B (GCN 5800), is 1hr away in RA and it is currently
taking all the time from this observation.

This circular is an official product of the Swift XRT Team.