GCN Circular 36851

C. Salvaggio (INAF-OAB), N. P. M. Kuin (UCL-MSSL),
D. M. Palmer (LANL), T. Sbarrato (INAF-OAB) and
B. Sbarufatti (INAF-OAB) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 03:27:12 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 240712A (trigger=1242223).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 122.369, -37.077 which is 
   RA(J2000) = 08h 09m 29s
   Dec(J2000) = -37d 04' 35"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve before T+8s after the
trigger is unavailable due to a telemetry outage.  The burst triggered
on the 8s timescale indicating that it is a long burst, but
no other duration information is presently available. 

The XRT began observing the field at 03:29:47 UT, 155 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 122.3378, -37.0923 which is equivalent to:
  RA(hh mm ss.s) = 8h09m21.08s
Dec(dd mm ss.s) = -37:05:32.21
with an uncertainty of 6.4 arcseconds (radius, 90% containment). This
location is 105 arcseconds from the BAT onboard position, within the BAT
error circle. 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 140 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 25% of
the BAT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
BAT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the large, but uncertain, extinction expected. 

Burst Advocate for this burst is C. Salvaggio (chiara.salvaggio AT inaf.it). 
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/)