GCN Circular 43318
Subject
GRB 260101A: Swift/UVOT Detection
Event
Date
2026-01-04T10:35:48Z (6 days ago)
From
noelklin@umbc.edu
Via
Web form
N. Klingler (NASA-GSFC / UMBC / CRESST II) and S. B. Cenko (GSFC) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 260101A 144 s after the BAT trigger (Cenko et al., GCN Circ. 43285). A source consistent with the enhanced XRT position (Evans et al., GCN Circ. 43289) is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 05:45:42.96 = 86.42898 (deg.)
Dec (J2000) = +63:35:32.1 = 63.59226 (deg.)
with an estimated uncertainty of 0.43 arc sec. (radius, 90% confidence).
Detections and 2-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
b 399.7 419.5 19.8 16.57 +/- 0.10
b 548.6 568.4 19.8 16.74 +/- 0.11
b 697.4 717.1 19.7 16.80 +/- 0.11
b 847.1 866.9 19.8 17.20 +/- 0.14
b 1031.0 1200.3 169.3 17.50 +/- 0.11
b 1329.9 1498.6 168.7 17.69 +/- 0.12
b 1628.4 1648.2 19.8 17.81 +/- 0.18
b 21638.8 22547.2 908.4 21.07 +/- 0.27
u 144.3 394.1 249.8 16.09 +/- 0.05
u 523.8 543.5 19.7 16.44 +/- 0.13
u 672.6 692.3 19.7 17.15 +/- 0.18
u 822.4 842.1 19.7 16.97 +/- 0.16
u 875.8 1025.6 149.8 17.12 +/- 0.08
u 1155.7 1324.8 169.1 17.86 +/- 0.18
u 1454.1 1623.5 169.4 17.86 +/- 0.18
u 95366.4 96053.5 687.1 >21.51
v 450.4 470.2 19.8 16.17 +/- 0.14
v 599.0 618.8 19.8 15.87 +/- 0.12
v 747.6 767.4 19.8 16.28 +/- 0.15
v 1081.4 1251.3 169.9 16.98 +/- 0.15
v 1380.2 1549.5 169.3 17.23 +/- 0.17
v 11438.4 12223.4 785.0 19.27 +/- 0.14
v 27138.9 28046.0 907.1 20.55 +/- 0.38
uvw1 499.5 816.9 317.4 >19.48
uvw1 1131.1 1599.0 467.9 >19.74
uvw1 34121.1 34973.5 852.4 >21.44
uvw2 425.8 743.0 317.2 >19.43
uvw2 1057.0 1525.2 468.2 >19.72
uvw2 10532.3 11432.0 899.7 >21.06
uvw2 22553.7 23374.5 820.8 >21.39
uvw2 100888.2 101273.5 385.3 >20.96
uvm2 474.7 643.2 168.5 >18.78
uvm2 1105.7 1424.3 318.6 >18.80
uvm2 28051.2 28842.6 791.4 >21.25
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.197 in the direction of the burst (Schlegel et al. 1998).