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GCN Circular 33016

GRB 221202A: Swift/UVOT Detection
2022-12-03T21:07:48Z (a year ago)
Paul Kuin at MSSL <>
Paul Kuin (MSSL-UCL) and R. Caputo (GSFC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 221202A
102 s after the BAT trigger (Caputo et al., GCN Circ. 33005).
A source consistent with the XRT position (Beardmore et al. GCN Circ. 33008)
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              102          733          186         20.66 +/- 0.20
v                  590         4820          216        >19.9
b                  516          709           39        >19.8
u                  260          857          285        >19.7
w1                 640          832           39        >20.8
m2                 615          808           39        >18.1
w2                 566         4635          235        >20.0

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.027 in the direction of the burst
(Schlegel et al. 1998).
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