[vsnet-grb-info 12833] GRB 130131A: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  14180
SUBJECT: GRB 130131A: Swift/UVOT Upper Limits
DATE:    13/02/02 15:19:38 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <siegel at swift.psu.edu>

M. H. Siegel and D. Grupe (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 130131A
68 s after the BAT trigger (Grupe et al., GCN Circ. 14156).
No optical afterglow consistent with the optical position (Tanver et al.,
GCN Circ 14157) or XRT position (Evans et al., GCN Circ. 14160)
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            68          217          147         >21.8
u_FC               280          529          246         >20.8
white               68         7570          839         >22.5
v                  609        18681         1378         >21.0
b                  535         7369          549         >21.7
u                  280        13670         1434         >22.0
w1                 658        12906         1434         >21.7
m2                1932        18851         1263         >21.3
w2                 758        17768         1336         >22.0

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.01 in the direction of the burst
(Schlegel et al. 1998).