NOTE: uvot_fluxes_wget.pl vrs. 2020-11-03a fem at 210620d05h27m38s399657usUT
NOTE: Source region spec. is: 319.71831 33.85044 3"
NOTE: Used archived uvot source position of 319.71831  33.85044  3.00
NOTE: position reference is GCN_Circ_30261
NOTE: A UVOT position was reported in GCN_Circ_30261
NOTE: Possible detection in uu at T+347.9
NOTE: Possible detection in wh at T+135.5
NOTE: Possible detection in bb at T+604.0
NOTE: Possible detection in w1 at T+729.1
NOTE: Possible detection in vv at T+679.1
NOTE: Possible detection in w2 at T+1532.9 sum

=========== Draft Upper Limit Circular ========

GRB 210619B: Swift/UVOT Upper Limits

N. P. M. Kuin (UCL-MSSL) and P. D'Avanzo (INAF-OAB)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 210619B
136 s after the BAT trigger (D'Avanzo et al., GCN Circ. 30261).
No optical afterglow consistent with the XRT position
*** POSITION REFERENCE is GCN_Notice ***
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           136          285          147         >14.6
u_FC               348          598          246         >15.5
white              136         1868          425         >15.8
v                  679         1750          113         >16.2
b                  604         1850          136         >17.1
u                  348         1825          363         >15.8
w1                 729         1800          117         >17.4
m2                 704         1776          117         >19.3
w2                 655         1726          136         >18.5

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.173 in the direction of the burst
(Schlegel et al. 1998).


=========== Draft Detection Circular ========

GRB 210619B: Swift/UVOT Detection

N. P. M. Kuin (UCL-MSSL) and P. D'Avanzo (INAF-OAB)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 210619B
136 s after the BAT trigger (D'Avanzo et al., GCN Circ. 30261).
A source consistent with the XRT position
*** POSITION REFERENCE is GCN_Notice ***
is detected in the initial UVOT exposures.

The preliminary UVOT position is:
    RA  (J2000) =  21:18:52.38 = 319.71825 (deg.)
    Dec (J2000) = +33:51:01.6  =  33.85044 (deg.)
with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence).

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

white              136          285          147         14.67 +/- 0.02
v                  679          699           19         15.59 +/- 0.10
b                  604          624           20         16.39 +/- 0.08
u                  348          598          246         15.60 +/- 0.03
w1                 729         1107           39         17.22 +/- 0.19
m2                 704         1776          117        >19.3
w2                 655         1726          136         19.20 +/- 0.31

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.173 in the direction of the burst
(Schlegel et al. 1998).