GCN Circular 28851
Subject
GRB 201104B: Swift/UVOT Detection
Event
Date
2020-11-06T09:41:59Z (6 years ago)
From
Samantha Oates at MSSL <samantha.oates@alumni.ucl.ac.uk>
S. R. Oates (U.Birmingham) and B. Sbarufatti (PSU)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 201104B
56 s after the BAT trigger (Sbarufatti et al., GCN Circ. 28825).
A source consistent with the XRT position (Sbarufatti et al. GCN Circ. 28825)
and UVOT position (Marshall et al. GCN Circ. 28827) is detected in the initial UVOT exposures.
Preliminary detections and 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white (FC) 56 206 147 17.98 +/- 0.05
white 20890 21385 484 >21.1
b 3718 3777 57 >19.0
u (FC) 268 459 188 18.72 +/- 0.16
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.048 in the direction of the burst
(Schlegel et al. 1998).