[vsnet-grb-info 25066] GRB 200219A: UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27165
SUBJECT: GRB 200219A: UVOT Upper Limits
DATE:    20/02/21 18:02:34 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <mhs18 at psu.edu>

M. H. Siegel (PSU) and A. Y. Lien (GSFC/UMBC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200219A
75 s after the BAT trigger (Lien et al., GCN Circ. 27125).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 27138)
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            75          225          147         >20.2
u_FC               287          537          246         >19.3
white               75        19365         1139         >21.2
v                  617        30839         1770         >19.7
b                  543        36572         2257         >20.9
u                  287        25105         2431         >20.7
w1                 666        40797         1248         >20.4
m2                 641        40734         2104         >20.4
w2                 592        28878          914         >20.2

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).