[vsnet-grb-info 17253] GRB 151118A: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18615
SUBJECT: GRB 151118A: Swift/UVOT Upper Limits
DATE:    15/11/18 12:31:35 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <siegel at swift.psu.edu>

M. H. Siegel (PSU) and Amaral-Rogers (U Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 151118A
70 s after the BAT trigger (Amaral-Rogers et al., GCN Circ. 18611).
No optical afterglow consistent with the XRT position
(Amaral-Rogers et al. GCN Circ. 18611)
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)           70          220          148         >20.6
u (fc)              282          532          246         >20.0
white               70          754          186         >20.8
v                  612          631           19         >18.3
b                  537          730           39         >19.3
u                  282          705          265         >19.9
w1                 661          680           19         >18.2
w2                 587          607           19         >17.9

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 1.10 in the direction of the burst
(Schlegel et al. 1998).