[vsnet-grb-info 17101] Trigger 659734: Swift detection of SAX J1750.8-2900 or other source near Galactic center

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18421
SUBJECT: Trigger 659734: Swift detection of SAX J1750.8-2900 or other source near Galactic center
DATE:    15/10/16 01:48:57 GMT
FROM:    David Palmer at LANL  <palmer at lanl.gov>

J. R. Cummings (NASA/UMBC), K. L. Page (U Leicester) and
T. Sakamoto (AGU) report on behalf of the Swift Team:

At 01:25:59 UT, the Swift Burst Alert Telescope (BAT) triggered and
located a burst with a position consistent with SAX J1750.8-2900
(trigger=659734).  Swift did not slew immediately to the location
due to higher priority observations. 
The BAT on-board calculated location is 
RA, Dec 267.600, -29.018 which is 
   RA(J2000) = 17h 50m 24s
   Dec(J2000) = -29d 01' 04"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single soft
FRED structure with a duration of about 8 sec.  The peak count rate
was ~1300 counts/sec (15-350 keV), at ~1 sec after the trigger. 

Although this BAT detection was consistent in position with
SAX J1750.8-2900 (within 71 arcseconds) the location near
the Galactic center (lon,lat = 0.47,-0.94 degrees) has a high
density of known and unknown sources, so the identification
cannot be confirmed.  Follow-up observations with the XRT
are planned to determine the origin of the burst.