NOTE: uvot_fluxes_wget.pl vrs. 2020-11-03a fem at 221227d06h59m23s417443usUT
NOTE: Source region spec. is: 22.90971 -41.52669 4"
NOTE: Used archived XRT position of  22.90971 -41.52669  4.00
NOTE: position reference is GCN_Circulars-33109
NOTE: Possible detection in wh at T+75.9

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

GRB 221226B: Swift/UVOT Upper Limits

***UBS*** (***INSTITUTION***) and S. B. Cenko (GSFC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 221226B
76 s after the BAT trigger (Cenko et al., GCN Circ. 33108).
No optical afterglow consistent with the XRT position
(Goad et al. GCN Circ. 33109)
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            76          226          147         >20.0
white               76         4198          344         >20.4
v                 4408         4608          197         >19.3
b                 3793         3993          197         >20.0
u                  288         5132          278         >20.1
w1                4818         5018          197         >20.0
m2                4613         4813          197         >19.5
w2                4204         4404          197         >20.0

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.017 in the direction of the burst
(Schlegel et al. 1998).


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

GRB 221226B: Swift/UVOT Detection

***UBS*** (***INSTITUTION***) and S. B. Cenko (GSFC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 221226B
76 s after the BAT trigger (Cenko et al., GCN Circ. 33108).
A source consistent with the XRT position
(Goad et al. GCN Circ. 33109)
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

white               76          226          147         20.54 +/- 0.22
v                 4408         4608          197        >19.3
b                 3793         3993          197        >20.0
u                  288         5132          278        >20.1
w1                4818         5018          197        >20.0
m2                4613         4813          197        >19.5
w2                4204         4404          197        >20.0

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.017 in the direction of the burst
(Schlegel et al. 1998).