TITLE: GCN CIRCULAR NUMBER: 17483 SUBJECT: Trigger 631946: Swift detection of H1745-203 DATE: 15/02/21 00:17:02 GMT FROM: Scott Barthelmy at NASA/GSFC S. D. Barthelmy (GSFC), J. R. Cummings (NASA/UMBC), V. D'Elia (ASDC), L. Izzo (URoma/ICRA) and T. Sakamoto (AGU) report on behalf of the Swift Team: At 23:38:50 UT, the Swift Burst Alert Telescope (BAT) triggered and located H1745-203 (trigger=631946). Swift will slew to the source at ~00:30 UT. The BAT on-board calculated location is RA, Dec 267.227, -20.379, which is RA(J2000) = 17h 48m 54s Dec(J2000) = -20d 22' 42" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). This was a 22-min image trigger, and as such there will be nothing visible in the real-time TDRSS light curve. This AT will be cancelled at about 02:30 UT. BAT has seen this source rising in flux since Feb 17. The BAT lightcurve can be seen at http://swift.gsfc.nasa.gov/results/transients/weak/H1745-203/