TITLE:   GCN CIRCULAR
NUMBER:  29914
SUBJECT: GRB 210430A: Swift detection of a burst
DATE:    21/04/30 13:19:58 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

B. Sbarufatti (PSU), A. Y. Lien (GSFC/UMBC) and
A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 10:42:10 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 210430A (trigger= 1046014).  Swift did not slew immediately
due to an observing constraint. 
The BAT on-board calculated location is 
RA, Dec 57.178, +45.074 which is 
   RA(J2000) = 03h 48m 43s
   Dec(J2000) = +45d 03' 31"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  With the currently available data from
~T-50 s to ~T+30 s, the BAT light curve showed a single-peaked
structure with a duration of about 10 sec.  The peak count rate
was ~500 counts/sec (15-350 keV), at ~2 sec after the trigger. 

The BAT position is sun-constrained for Swift until July 8 2021,
there will be no XRT or UVOT followup before this time. 

Burst Advocate for this burst is B. Sbarufatti (bxs60 AT psu.edu). 
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/)