GCN Circular 21835
Subject
GRB 170906C: Swift/UVOT Upper Limits
Date
2017-09-06T16:50:16Z (7 years ago)
From
Mike Siegel at PSU/Swift MOC <siegel@swift.psu.edu>
M. H. Siegel (PSU) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 170906C
1296 s after the BAT trigger (Siegel et al., GCN Circ. 21826).
No optical afterglow consistent with the XRT position
(Evans et al. GCN Circ. 21828)
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 1296 1446 147 >21.6
white 1296 2585 284 >21.4
v 1578 2635 136 >19.4
b 1504 2913 333 >19.9
u 1479 2708 156 >20.6
w1 1454 2684 156 >19.9
m2 2467 2487 19 >17.8
w2 2591 2611 19 >19.0
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).