[vsnet-grb-info 11125] GRB 111107A: Swift/UVOT Afterglow Analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  12540
SUBJECT: GRB 111107A: Swift/UVOT Afterglow Analysis
DATE:    11/11/07 14:21:50 GMT
FROM:    Paul Kuin at MSSL  <npkuin at gmail.com>

N. P. M. Kuin (MSSL-UCL) and M. H. Siegel (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of
GRB 111107A  73 s after the BAT trigger (Siegel et al.,
GCN Circ. 12534).

Preliminary detections and 3-sigma upper limits using the UVOT
photometric system (Poole et al. 2008, MNRAS, 383, 627)
for the early exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

white               73          223          147         19.45 +/- 0.10
v                  615         1755          136        >18.7
b                  540         1681          117        >20.0
u                  285         1656          343        >19.9
w1                 664         1631          117        >19.2
m2                 639         5231          299        >19.7
w2                 590         1730          136        >20.0

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.14 in the direction of the burst
(Schlegel et al. 1998).