TITLE:   GCN CIRCULAR
NUMBER:  21849
SUBJECT: Swift Triggered on MAXI J1535-571
DATE:    17/09/08 08:37:31 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

S. D. Barthelmy (GSFC), C. Gronwall (PSU) and K. L. Page (U Leicester)
report on behalf of the Swift Team:

At 08:13:48 UT, the Swift Burst Alert Telescope (BAT) triggered and
located MAXI J1535-571 (trigger=771371).  The BAT on-board calculated location
is RA, Dec 233.847, -57.233, which is 
   RA(J2000)  =  15h 35m 23s
   Dec(J2000) = -57d 13' 59"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows several small peaks
with a total duration of about 60 sec.  The peak count rate
was ~1000 counts/sec (15-350 keV), at ~20 sec after the trigger. 

Swift did not automatically slew to the trigger because of a higher
merit planned observation. However, about 100 s later, pre-planned
observations of MAXI J1735-571 began, and data from that observation
will be available when downlinked.