GCN Circular 12716

D. Grupe (PSU) reports on behalf of the Swift-XRT team:

We have analyzed 2.3 ks of XRT data for the IPN-detected burst: GRB
111222A (Hurley et al. et al. GCN Circ. 12714
Not found
 
 
), from 92.9 ks to 95.2 ks
after the  IPN trigger. The data are entirely in Photon Counting (PC)
mode.  An X-ray source is detected within the IPN error circle. Using
1964 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 = 179.21977, +69.07116 which is
equivalent to:

RA (J2000): 11h 56m 52.74s
Dec(J2000): +69d 04' 16.2"

with an uncertainty of 3.1 arcsec (radius, 90% confidence). This
position is 322 arcsec from the IPN position.  We cannot determine at
the present time whether the source is fading.

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.5 (+4.9, -4.3). The
best-fitting absorption column is  consistent with the Galactic value
of 1.7 x 10^20 cm^-2 (Kalberla et al. 2005). The counts to observed
(unabsorbed) 0.3-10 keV flux conversion factor deduced from this
spectrum  is 6.8 x 10^-11 (7.0 x 10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     0 (+2.1, -0) x 10^22 cm^-2
Galactic foreground: 1.7 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index:	     1.5 (+4.9, -4.3)

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020194.

This circular is an official product of the Swift-XRT team.