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GCN Circular 23303

GRB 181003A: Swift/UVOT Upper Limits
2018-10-03T17:47:56Z (6 years ago)
Sam LaPorte at PSU <>
GRB 181003A: Swift/UVOT Upper Limits

S. J. LaPorte (PSU) and A. P. Beardmore (U. Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 181003A
3095 s after the BAT trigger (Beardmore et al., GCN Circ. 23295).
No optical afterglow consistent with the XRT position
(Evans et al. GCN Circ. 23296)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

b              5040         5240           196            >20.83  
uvm2           3452         3652           196            >19.46 
u              3862         3902            39            >19.19 
v              3427         3447           196            >19.79 
uvw1           3658         3857           196            >19.85
uvw2           5451         5597           144            >19.37 
white          3091         3240           294            >21.73  

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.01 in the direction of the burst
(Schlegel et al. 1998).
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