TITLE:   GCN CIRCULAR
NUMBER:  6352
SUBJECT: GRB 070427: Swift detection of a burst
DATE:    07/04/27 08:48:05 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

G. Sato (GSFC/ISAS), S. Campana (INAF-OAB), P. A. Evans (U Leicester),
C. Guidorzi (Univ Bicocca&INAF-OAB), C. B. Markwardt (GSFC/UMD),
P. T. O'Brien (U Leicester), J. P. Osborne (U Leicester),
K. L. Page (U Leicester), D. M. Palmer (LANL),
R. L. C. Starling (U Leicester) and H. Ziaeepour (UCL-MSSL) report on
behalf of the Swift Team:

At 08:31:08 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 070427 (trigger=277356).  This burst was too close to
the Sun (42 degrees) for Swift to slew to it. 
The BAT on-board calculated location is 
RA, Dec 28.862, -27.633 which is 
   RA(J2000) = 01h 55m 27s
   Dec(J2000) = -27d 37' 57"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multiple-peaked
structure with a duration of about 15 sec.  The peak count rate
was ~3500 counts/sec (15-350 keV), at ~5 sec after the trigger. 

The GRB will become observable by the XRT and UVOT on May 5.