GCN Circular 27352

GRB 200306C: Swift/UVOT Detection

J. D. Gropp (PSU) reports on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200306C
118 s after the BAT trigger (Gropp et al., GCN Circ. 27326
Not found
 
 
).

A fading source consistent with the positions reported by
FRAM-ORM (Jelinek et al., GCN Circ. 27238
Not found
 
 
),
BOOTES-1 (Hu et al., GCN Circ. 27329
Not found
 
 
),
SAO RAS (Moskvitin et al., GCN Circ. 27333
Not found
 
 
)
Liverpool Telescope (Izzo et al., GCN Circ 27334)
and OSN (Kann et al., GCN Circ. 27335
Not found
 
 
)
is detected in the initial UVOT exposures.

The preliminary UVOT position is:
    RA  (J2000) =  13:14:13.46 = 198.55607 (deg.)
    Dec (J2000) = +11:16:11.7  =  11.26992 (deg.)
with an estimated uncertainty of 0.43 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

u_fc           141             390               245
16.90+-0.05
u                899           1049               147
18.39+-0.16


The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).