TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4644 SUBJECT: Swift BAT Trigger 180151: Swift XRT source detection DATE: 06/02/04 03:24:20 GMT FROM: David Burrows at PSU/Swift The Swift satellite slewed at 00:45:26 UT on 4 Feb 2006 to the position of the BAT trigger 180151 (Retter et al. 2006, GCN 4641), 2990 s after the trigger. Although it is still not clear whether this trigger is from a real astrophysical source, we find a faint, possibly fading, and uncataloged X-ray source at the following position: RA(J2000) = 6h 54m 3.9s Dec(J2000) = +71d 48' 39" The estimated uncertainty is 6 arcseconds. The exposure time was 2.5 ks. This source is 44 arcseconds from the reported BAT position for trigger 180151. This position includes the new XRT boresight, but was processed using proprietary software in an effort to distribute the position as soon as possible. A more definitive statement of the nature of this source will be distributed following analysis of the XRT data processed through the normal XRT pipeline software at the SDC.