GCN Circular 16123
Subject
GRB140419A: UVOT detects fading afterglow in white but not in u filter
Date
2014-04-19T07:56:22Z (11 years ago)
From
Paul Kuin at MSSL <npkuin@gmail.com>
NPM Kuin (MSSL-UCL), and F. E. Marshall (NASA/GSFC) report on behalf of
the Swift Team:
UVOT started observing GRB 140419A starting 96 seconds after the BAT
trigger.
The initial finding chart exposures with the White and U filter show a
fading source in the white filter which we identify with the afterglow:
The estimated magnitudes are as follows:
filter starttime endtime magnitude error
wh 96 246 16.01 0.06
u 308 558 >19.6
wh 862 1012 17.96 0.09.
The source is not seen in the u filter, which suggests a redshift larger
then
2.8.
No correction has been made for the expected extinction corresponding to
E(B-V) of 0.03.