[vsnet-grb-info 12977] GRB 130313A: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  14314
SUBJECT: GRB 130313A: Swift/UVOT Upper Limits
DATE:    13/03/15 21:41:57 GMT
FROM:    Tyler Pritchard at PSU  <tapritchard at astro.psu.edu>

T. A. Pritchard (PSU) and B. P. Gompertz (U Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 130313A
81 s after the BAT trigger (Gompertz et al., GCN Circ. 14293).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 14300)
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            81          231          147         >20.6
u_FC               293          543          246         >20.3
white               81        17899         2332         >22.4
v                  625        22348         1681         >20.4
b                  550        16987         1327         >21.4
u                  293         6955          697         >20.3
w1                 674         6750          471         >20.9
m2                 649         6545          413         >21.0
w2                 600        18671         2110         >21.5

The magnitudes in the table 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).