GCN Circular 26053

GRB 191019A: Swift/UVOT Detection

S. J. LaPorte (PSU) and K. K. Simpson (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 191019A
3294 s after the BAT trigger (Simpson et al., GCN Circ. 26031
Not found
 
 
).
A fading source consistent with the XRT position
(Evans et al. GCN Circ. 26034
Not found
 
 
)
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

b               4541          4741             196
19.55+-0.30
uvm2        5361          5561             196              >19.20
u               4336          4536             196              >19.43
v               5156          5356              196             >18.75
uvw1        4131          4331              196              >19.13
uvw2        4952          5151              196              >19.28
white        4746          4946              196                19.66+-0.20

white      27982        28668              668                20.27+-0.18

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.04 in the direction of the burst
(Schlegel et al. 1998). Additionally, these magnitudes likely include a
contribution
from the probable host-galaxy, as reported by TSHAO (Reva et al., GCN Circ.
26036
Not found
 
 
),
NOT (Fynbo et al., GCN Circ. 26041
Not found
 
 
), and GROND (Guelbenzu et al. GCN Circ.
26042
Not found
 
 
).