GCN Circular 29403

Subject

GRB 210205A: Swift/UVOT Upper Limits

Event

Date

2021-02-05T18:16:08Z (5 years ago)

From

Alexander Belles at PSU/Swift <aub1461@psu.edu>

A. Belles (PSU) and S. Dichiara (NASA/GSFC/UMCP)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 210205A
139 s after the BAT trigger (Dichiara et al., GCN Circ. 29397Loading...
 
 ).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 29399Loading...
 
 )
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 first
finding chart (FC) exposure and subsequent exposures are:

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

white_FC           139          289          147         >20.5
white              139         4057          344         >20.6
v                 4268         4468          197         >19.4
b                 3652         5159          265         >20.1
u                  297         5084          255         >19.7
w1                4678         4878          197         >19.9
m2                4473         4673          197         >20.8
w2                4063         4263          197         >19.3

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.716 in the direction of the burst
(Schlegel et al. 1998).