TITLE:   GCN CIRCULAR
NUMBER:  37662
SUBJECT: GRB 241002A: Swift detection of a burst
DATE:    24/10/02 01:09:25 GMT
FROM:    K.L. Page at U Leicester <klp5@leicester.ac.uk>

R. Caputo (GSFC), R. Gupta (NASA GSFC), M. J. Moss (GSFC),
K. L. Page (U Leicester), D. M. Palmer (LANL) and
B. Sbarufatti (INAF-OAB) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 00:50:22 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 241002A (trigger=1257556).  Swift slewed immediately to the burst.
The BAT on-board calculated location is 
RA, Dec 140.955, +39.854 which is 
   RA(J2000) = 09h 23m 49s
   Dec(J2000) = +39d 51' 15"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex
structure with a duration of about 20 sec.  The peak count rate
was ~1900 counts/sec (15-350 keV), at ~0 sec after the trigger.

The XRT began observing the field at 00:52:09.0 UT, 106.1 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 140.9500, 39.8324 which is equivalent to:
   RA(J2000)  = 09h 23m 48.00s
   Dec(J2000) = +39d 49' 56.6"
with an uncertainty of 5.8 arcseconds (radius, 90% containment). This
location is 78 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to determine the column
density using X-ray spectroscopy.

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 115 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image processing
FAILED because of no aspect solution. Data from the list of sources generated
on-board are not available at this time. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.011.

Burst Advocate for this burst is R. Caputo (regina.caputo AT nasa.gov).
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/)