[vsnet-grb-info 12227] GRB 120807A: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  13616
SUBJECT: GRB 120807A: Swift/UVOT Upper Limits
DATE:    12/08/10 14:32:49 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <siegel at swift.psu.edu>

GRB 120807A: Swift/UVOT Upper Limits

M. H. Siegel (PSU) and F. E. Marshall (NASA/GSFC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 120807A
75 s after the BAT trigger (Marshall et al., GCN Circ. 13602).
No optical afterglow consistent with the XRT position (Beardmore et al., 
GCN Circ. 13603) 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            75          225          147         >20.6
u_FC               288          537          246         >20.4
white               75         1884          431         >21.8
v                  618         1935          156         >19.6
b                  543         1860          136         >20.4
u                  288         1835          363         >20.7
w1                 668         1810          136         >20.3
m2                1591         1611           19         >18.8
w2                 593         1910          117         >19.9

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 1.41 in the direction of the burst
(Schlegel et al. 1998).