GCN Circular 18150
Subject
GRB 150817A: Swift/UVOT Upper Limits
Date
2015-08-17T16:34:51Z (9 years ago)
From
Frank Marshall at GSFC <femarsha@khamseen.gsfc.nasa.gov>
F. E. Marshall (NASA/GSFC) and V. D'Elia (ASDC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 150817A
3955 s after the BAT trigger (D'Elia et al., GCN Circ. 18143).
No optical afterglow consistent with the enhanced X-ray
position (Osborne et al. GCN Circ. 18146) or
the optical position (Butler et al. GCN Circ. 18145)
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 first
finding chart (FC) exposure and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_FC 3955 4104 147 >20.5
white 3955 12079 930 >21.4
v 4111 28678 1278 >20.9
b 4932 17880 1723 >21.7
u 4727 23627 2613 >21.7
w1 4522 22957 2144 >21.0
w2 26865 27765 886 >20.5
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.48 in the direction of the burst
(Schlegel et al. 1998).