[vsnet-grb-info 23930] GRB 191017B: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  26029
SUBJECT: GRB 191017B: Swift/UVOT Upper Limits
DATE:    19/10/18 14:37:28 GMT
FROM:    Sam LaPorte at PSU  <sjl5346 at psu.edu>

GRB 191017B: Swift/UVOT Upper Limits

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

The Swift/UVOT began settled observations of the field of GRB 191017B
302 s after the BAT trigger (Sbarufatti et al., GCN Circ. 26021).
No optical afterglow consistent with the XRT position
(Goad et al. GCN Circ. 26022)
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           302          452          147         >18.9
white              302         1010          334         >19.1
v                  460         4806          255         >18.1
b                  558          752           39         >18.3
u                  533          727           39         >18.9
w1                 509          702           39         >18.2
m2                 484          852           39         >18.6
w2                 609         4601          235         >20.0

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.11 in the direction of the burst
(Schlegel et al. 1998).