GCN Circular 30247
Subject
GRB 210610B: Swift/UVOT Detection
Event
Date
2021-06-17T13:37:18Z (5 years ago)
From
Mike Siegel at PSU/Swift MOC <mhs18@psu.edu>
M. H. Siegel (PSU), M. Baer (PSU) and K. L. Page (U. Leicester)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 210610B
92 s after the BAT trigger (Page et al., GCN Circ. 30170). A fading source consistent
with the XRT position (Osborne et al. GCN Circ. 30189) and the previously reported
optical counterpart (Kumar et al., GCN Circ. 30174; Rumyantsev et al. GCN Circ.
30175; Hu et al., GCN Circ. 30177; de Wet et al., GCN Circ. 30180; Romanov, GCN Circ.
30181; Fynbo et al., GCN Circ. 30182; Moskvitin, GCN Circ. 30187; Fu et al., GCN Circ.
30188) is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 16:15:40.40 = 243.91833 (deg.)
Dec (J2000) = +14:23:56.9 = 14.39915 (deg.)
with an estimated uncertainty of 0.42 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 (fc) 92 242 147 13.63+/-1.10
white 584 1355 225 15.24+/-0.02
white 172034 172423 377 20.22+/-0.14
white 286441 292869 328 20.71+/-0.23
white 452008 515231 4066 21.69+/-0.16
v 634 1405 97 15.63+/-0.05
v 6631 51903 659 18.26+/-0.09
b 560 1331 77 15.78+/-0.04
b 81150 133027 865 20.08+/-0.14
u (fc) 304 554 245 13.86+/-0.03
u 707 1306 58 14.93+/-0.04
u 4850 5040 186 16.68+/-0.05
u 45786 46567 761 18.06+/-0.05
u 131743 132650 885 20.00+/-0.18
u 365977 418267 3970 21.42+/-0.29
uvw1 683 1282 58 14.51+/-0.06
uvw1 4645 4845 196 16.26+/-0.07
uvw1 7041 45779 989 17.54+/-0.06
uvw1 125974 137480 881 19.53+/-0.20
uvw1 200561 247267 1111 19.95+/-0.24
uvm2 6836 7036 196 16.61+/-0.10
uvw2 783 1034 38 15.05+/-0.09
uvw2 50521 51421 885 18.44+/-0.10
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.044 in the direction of the burst
(Schlegel et al. 1998).