[vsnet-grb-info 21564] GRB 190109A: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  23663
SUBJECT: GRB 190109A: Swift/UVOT Upper Limits
DATE:    19/01/09 20:36:24 GMT
FROM:    Kira Simpson at PSU  <kira.simpson1984 at gmail.com>

GRB 190109A: Swift/UVOT Upper Limits

K. K. Simpson (PSU) and J. D. Gropp (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 190109A
181 s after the BAT trigger (Gropp et al., GCN Circ. 23642).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 23644)
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           181          331          147         >99.0
u_FC               340          590          246         >17.3
white              181        12997         1291         >99.0
v                  670         6867          490         >16.8
b                  596        18739         1727         >18.6
u                  340        24226         2551         >17.5
w1                 720        23954         2223         >17.4
m2                 695        23048         1357         >18.1
w2                 646         6662          491         >17.9

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.05 in the direction of the burst
(Schlegel et al. 1998).