[vsnet-grb-info 19385] GRB 170516A: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  21099
SUBJECT: GRB 170516A: Swift/UVOT Upper Limits
DATE:    17/05/16 22:02:21 GMT
FROM:    Paul Kuin at MSSL  <npkuin at gmail.com>

N. P. M. Kuin (UCL-MSSL) and A. Y. Lien (GSFC/UMBC) report
on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field
of GRB 170516A 87 s after the BAT trigger (Lien et al., GCN Circ.
21097). No optical afterglow consistent with the XRT position
(Lien et al. GCN Circ. 21097) 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            87          237          147         >20.1
white               87         5703          541         >21.1
v                 4478         6113          393         >19.8
b                 3863         5498          393         >20.6
u                  299         5293          379         >19.4
w1                4888         5088          197         >19.4
m2                4683         6222          299         >20.5
w2                4274         5909          393         >20.5

The magnitudes in the table are not corrected for the
Galactic extinction due to the reddening of E(B-V) = 0.03
in the direction of the burst (Schlegel et al. 1998).