[vsnet-grb-info 14213] GRB 131127A: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15527
SUBJECT: GRB 131127A: Swift/UVOT Upper Limits
DATE:    13/11/28 11:56:24 GMT
FROM:    Alice Breeveld at MSSL-UCL  <a.breeveld at ucl.ac.uk>

A. A. Breeveld (UCL-MSSL) and C. B. Markwardt (NASA/GSFC) report on 
behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 131127A 
102 s after the BAT trigger (Markwardt et al., GCN Circ. 15516).
No optical afterglow consistent with the XRT position (Evans et al. GCN 
Circ. 15520) nor the RATIR position (Butler et al. GCN Circ. 15525) 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           102          252          147         >21.4
u_FC               315          565          246         >20.6
white              102         6711          746         >22.3
v                  645         7024          373         >20.3
b                  571         6506          452         >21.2
u                  315         6300          678         >21.1
w1                 694         6095          432         >20.6
m2                 669         5890          269         >20.1
w2                 621         6916          471         >20.9

The magnitudes in the table are not corrected for the Galactic 
extinction due to the reddening of E(B-V) = 0.14 in the direction of the 
burst (Schlegel et al. 1998).