[vsnet-grb-info 14683] GRB 140318A: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15997
SUBJECT: GRB 140318A: Swift/UVOT Upper Limits
DATE:    14/03/19 14:07:38 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <siegel at swift.psu.edu>

B. Porterfield (PSU) and Cenko (GSFC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 140318A
132 s after the BAT trigger (Cenko et al., GCN Circ. 15986).
No optical afterglow consistent with the XRT position
(Cenko et al. GCN Circ. 15986) or NOT position (Schulze et al., GCN 
Circ 15987) 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           132          282          147         >21.2
white              132         5340          541         >21.9
v                 4115         5750          393         >19.6
b                 3499         5135          393         >20.9
u                 4730         4930          197         >20.1
w1                4525         6063          298         >20.5
m2                4320         5955          393         >21.2
w2                3910         5546          393         >20.7

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).