GCN Circular 16187
Subject
GRB 140428A: Swift/UVOT Upper Limits
Date
2014-04-29T21:13:07Z (10 years ago)
From
Frank Marshall at GSFC <femarsha@khamseen.gsfc.nasa.gov>
F. E. Marshall (NASA/GSFC) and D. Kocevski (NASA/GSFC/ORAU)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 140428A
104 s after the BAT trigger (Kocevski et al., GCN Circ. 16177).
No optical afterglow consistent with the optical position
(Perley, GCN_Circ. 16180) is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white 104 254 147 >21.2
v 5454 5653 197 >20.3
b 4838 5039 197 >21.4
u 264 271 7 >19.5
uw1 5864 6030 197 >20.5
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.009 in the direction of the burst
(Schlegel et al. 1998).