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GCN Circular 18785

Trigger 668949: Swift detection of V 404 Cyg
2015-12-31T17:31:09Z (8 years ago)
Kim Page at U.of Leicester <>
S. D. Barthelmy (GSFC), V. D'Elia (ASDC), L. Izzo (URoma/ICRA),
J. A. Kennea (PSU), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (NASA/GSFC), K. L. Page (U Leicester) and
M. H. Siegel (PSU) report on behalf of the Swift Team:

At 17:17:58 UT, the Swift Burst Alert Telescope (BAT) triggered and
located V 404 Cyg (trigger=668949).  Swift did not slew because of a higher
merit value target already being observed.  The BAT on-board calculated location
is RA, Dec 305.996, +33.859, which is 
   RA(J2000)  =  20h 23m 59s
   Dec(J2000) = +33d 51' 34"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows several peaks
with a total duration of about 40 sec.  The peak count rate
was ~1100 counts/sec (15-350 keV), at ~0 sec after the trigger.
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