NOTE: uvot_fluxes_wget.pl vrs. 2018-11-07 fem at 200201d10h56m33s695940usUT
NOTE: Source region spec. is: 3.09403 51.11678 3"
NOTE: Used archived uvot source position of   3.09403  51.11678  3.00
NOTE: position reference is GCN_Circ_26953
NOTE: A UVOT position was reported in GCN_Circ_26953
NOTE: Possible detection in uu at T+289.9
NOTE: Possible detection in wh at T+77.5
NOTE: Possible detection in bb at T+3665.6
NOTE: Possible detection in w1 at T+4692.4
NOTE: Possible detection in vv at T+4281.2
NOTE: Possible detection in w2 at T+4076.1
NOTE: Possible detection in m2 at T+4485.9

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

GRB 200131A: Swift/UVOT Upper Limits

N. P. M. Kuin (UCL-MSSL) and B. Sbarufatti (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200131A
78 s after the BAT trigger (Sbarufatti et al., GCN Circ. 26953).
No optical afterglow consistent with the XRT position
(Goad et al. GCN Circ. 26956)
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            78          227          147         >15.4
white               78         5508          541         >17.0
v                 4281         5919          393         >18.9
b                 3666         5303          393         >19.1
u                  290         5097          229         >17.6
w1                4692         9741          598         >18.5
m2                4486         6124          393         >18.5
w2                4076         5714          393         >18.6

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.17 in the direction of the burst
(Schlegel et al. 1998).


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

GRB 200131A: Swift/UVOT Detection

N. P. M. Kuin (UCL-MSSL) and B. Sbarufatti (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200131A
78 s after the BAT trigger (Sbarufatti et al., GCN Circ. 26953).
A source consistent with the XRT position
(Goad et al. GCN Circ. 26956)
is detected in the initial UVOT exposures.

The preliminary UVOT position is:
    RA  (J2000) =  00:12:22.57 =   3.09405 (deg.)
    Dec (J2000) = +51:07:00.3  =  51.11675 (deg.)
with an estimated uncertainty of 0.42 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

white               78          227          147         15.47 +/- 0.02
v                 4281         5919          393         19.57 +/- 0.28
b                 5103         5303          197         19.53 +/- 0.16
u                  290          323           32         16.09 +/- 0.08
w1                4692         4892          197         18.48 +/- 0.18
m2                4486         6124          393         18.98 +/- 0.20
w2                4076         5714          393         19.06 +/- 0.19

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.17 in the direction of the burst
(Schlegel et al. 1998).