GCN Circular 4776

J. A. Kennea, D. N. Burrows (PSU), G. Cusumano (INAF-Pa), and G. 
Tagliaferri (INAF-OAB) report on behalf of the Swift XRT team:

The Swift XRT observed the position of GRB 060218 (Cusumano et al., GCN 
4775
Not found
 
 
) beginning at 03:37:04 UT, 153 s after the BAT trigger. The 
on-board centroiding algorithm did not find a source. Ground-processing 
of the data was delayed, but we have now partially analyzed data from 
the first two orbits, using Level 0 data from the MOC. The XRT was in 
Windowed Timing mode for the entire first orbit and therefore no 
position is available from that orbit. The XRT switched into PC mode 
during the second orbit, during which we clearly detect a bright, fading 
point source located at:

RA(J2000): 03h 21m 39.7s
Dec(J2000): 16d 52' 01.33"

We estimate the uncertainty to be about 5 arcseconds (90% confidence 
radius). This position lies 39 arcseconds from the BAT position reported 
in GCN 4775
Not found
 
 
. A full analysis of the XRT data will follow.

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