GCN Circular 28827
Subject
GRB 201104B: Swift/UVOT Detection
Date
2020-11-04T20:16:09Z (3 years ago)
From
Frank Marshall at Swift/UVOT <marshall@milkyway.gsfc.nasa.gov>
F. E. Marshall (NASA/GSFC), S. R. Oates (U.Warwick) 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)
is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 00:20:51.65 = 5.21520 (deg.)
Dec (J2000) = +07:50:29.4 = 7.84150 (deg.)
with an estimated uncertainty of 0.43 arc sec. (radius, 90% confidence).
Preliminary detections 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 56 206 147 18.63 +/- 0.06
u 268 459 188 19.45 +/- 0.23
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.045 in the direction of the burst
(Schlegel et al. 1998).