[vsnet-grb-info 13915] GRB 130912A: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15229
SUBJECT: GRB 130912A: Swift/UVOT Upper Limits 
DATE:    13/09/15 20:52:11 GMT
FROM:    Margaret Chester at PSU  <chester at astro.psu.edu>

M. M. Chester (PSU) and V. D'Elia (ASDC) report on behalf of the 
Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 130912A
99 s after the BAT trigger (D'Elia et al., GCN Circ. 15212).
No optical afterglow consistent with the enhanced XRT position 
(Beardmore et al. GCN Circ. 15217) 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) exposures and subsequent exposures are:

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

white_FC            99          249          147         >20.7
u_FC               311          561          246         >20.2
white               99         6848          785         >21.4
v                  640        23984         1395         >20.3
b                  566        30470         1907         >21.6
u                  311        36236         3907         >21.6
w1                 690        35508         3836         >22.1
m2                1070        34601         2827         >21.8
w2                 616        23070         1376         >21.6

The magnitudes in the table are not corrected for the Galactic 
extinction due to the reddening of E(B-V) = 0.28 in the direction 
of the burst (Schlegel et al. 1998).