TITLE: GCN CIRCULAR NUMBER: 22710 SUBJECT: GRB 180512A: Swift detection of a burst DATE: 18/05/12 23:01:48 GMT FROM: Alex Deich at Penn State U A. Deich (PSU), S. D. Barthelmy (GSFC), D. N. Burrows (PSU), J.D. Gropp (PSU), S. J. LaPorte (PSU), A. Y. Lien (GSFC/UMBC) and F. E. Marshall (NASA/GSFC) report on behalf of the Neil Gehrels Swift Observatory Team: At 22:01:47 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 180512A (trigger=832119). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 201.953, +21.406 which is RA(J2000) = 13h 27m 49s Dec(J2000) = +21d 24' 23" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a multi-peaked structure with a duration of about 550 sec. The main pulse starts at ~T+400 s and ends at ~T+550 s. The peak count rate was ~1000 counts/sec (15-350 keV), at ~500 sec after the trigger. The XRT began observing the field at 22:05:20.1 UT, 213.0 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 201.93846, 21.40271 which is equivalent to: RA(J2000) = 13h 27m 45.23s Dec(J2000) = +21d 24' 09.8" with an uncertainty of 4.4 arcseconds (radius, 90% containment). This location is 50 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at http://www.swift.ac.uk/sper. We cannot determine whether the source is fading at the present time. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 1.73 x 10^20 cm^-2 (Willingale et al. 2013). No UVOT data are available at this time. Burst Advocate for this burst is A. Deich (aud375 AT psu.edu). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)