TITLE:   GCN CIRCULAR
NUMBER:  35501
SUBJECT: GRB 240109A: Swift detection of a short burst
DATE:    24/01/09 04:15:10 GMT
FROM:    David Palmer at LANL <palmer@lanl.gov>


S. Dichiara (PSU), D. M. Palmer (LANL) and M. H. Siegel (PSU) report
on behalf of the Neil Gehrels Swift Observatory Team:

At 04:01:35 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 240109A (trigger=1207446).  Due to a Sun constraint,
Swift did not slew immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 301.318, +16.578 which is 
   RA(J2000) = 20h 05m 16s
   Dec(J2000) = +16d 34' 39"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single spike
structure with a duration of about 0.25 sec.  The peak count rate
was ~4000 counts/sec (15-350 keV), at ~0.1 sec after the trigger. 

Due to a Sun observing constraint, Swift cannot slew to the BAT
position until 00:14 UT on 2024 March 01. There will thus be no XRT or
UVOT data for this trigger before this time. 

Burst Advocate for this burst is S. Dichiara (sbd5667 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/)