[vsnet-grb-info 7503] GRB 090401: Swift detection of a burst

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  9062
SUBJECT: GRB 090401: Swift detection of a burst
DATE:    09/04/01 00:23:21 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott at lheamail.gsfc.nasa.gov>

P. Schady (MSSL-UCL), S. D. Barthelmy (GSFC), N. Gehrels (NASA/GSFC),
S. T. Holland (CRESST/USRA/GSFC), H. A. Krimm (CRESST/GSFC/USRA),
C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC),
K. L. Page (U Leicester), D. M. Palmer (LANL), A. M. Parsons (GSFC),
B. A. Rowlinson (U Leicester) and L. Vetere (PSU) report on behalf of
the Swift Team:

At 00:00:59 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090401 (trigger=348128).  The BAT on-board calculated 
location is RA, Dec 350.909, +29.767 which is 
   RA(J2000)  =  23h 23m 38s
   Dec(J2000) = +29d 46' 00"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a small peak at
~T+30 sec and then two large peaks at ~T+100 and ~T+120 sec. 
The peak count rate was ~4000 counts/sec (15-350 keV), at ~120 sec
after the trigger. 

Due to an observing constraint, Swift cannot slew to
the BAT position. It will not be possible to observe
until 2nd May due to a sun constraint. There will thus 
be no XRT or UVOT data for this trigger. 

Burst Advocate for this burst is P. Schady (ps AT mssl.ucl.ac.uk). 
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/too.html.)