GCN Circular 10990
Subject
GRB 100725B: Swift/UVOT Upper Limits
Date
2010-07-25T23:00:52Z (14 years ago)
From
Tyler Pritchard at PSU <tapritchard@astro.psu.edu>
GRB 100725B: Swift/UVOT Upper Limits
T. A. Pritchard (PSU) and W. H. Baumgartner (GSFC/UMBC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 100725B
87 s after the BAT trigger (Baumgartner et al., GCN Circ. 10983).
No optical afterglow consistent with the XRT position
(Goad et al., GCN Circ. 10986) is detected in the initial UVOT
exposures. Preliminary 3-sigma upper limits using the UVOT
photometric system (Poole et al. 2008, MNRAS, 383, 627) for the
first finding chart (FC) exposure and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white(FC) 87 237 147 >20.8
u(FC) 300 549 246 >20.4
white 87 6844 664 >21.4
v 629 5882 244 >19.6
b 555 6703 432 >20.5
u 300 6498 659 >20.2
w1 678 6293 432 >20.3
m2 653 6088 432 >20.1
w2 605 5677 255 >20.1
The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.09 in the direction of the burst
(Schlegel et al. 1998).