NOTE: uvot_fluxes_wget.pl vrs. 2018-01-16 fem at 180729d06h36m38s260842usUT
NOTE: Source region spec. is: 253.56512 -54.04453 4"
NOTE: Used archived XRT position of 253.56512 -54.04453  4.00
NOTE: position reference is GCN_Circulars-23051
NOTE: Possible detection in uu at T+1970.5
NOTE: Possible detection in wh at T+1740.5
NOTE: Possible detection in bb at T+1995.4
NOTE: Possible detection in w1 at T+1946.1
NOTE: Possible detection in vv at T+1896.9
NOTE: Possible detection in w2 at T+2045.1
NOTE: Possible detection in m2 at T+1921.3

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

GRB 180728A: Swift/UVOT Upper Limits

S. J. LaPorte (PSU) and R. L. C. Starling (U. Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 180728A
1740 s after the BAT trigger (Starling et al., GCN Circ. 23046).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 23051)
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          1740         1890          147         >16.2
white             1740        15163          887         >16.7
v                 1897        32152         1376         >17.3
b                 1995        20909         1450         >17.7
u                 1970        26655         2317         >17.1
w1                1946        37525         3417         >17.3
m2                1921        36948         2481         >17.8
w2                2045        31239         1318         >17.5

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.29 in the direction of the burst
(Schlegel et al. 1998).


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

GRB 180728A: Swift/UVOT Detection

S. J. LaPorte (PSU) and R. L. C. Starling (U. Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 180728A
1740 s after the BAT trigger (Starling et al., GCN Circ. 23046).
A source consistent with the XRT position
(Osborne et al. GCN Circ. 23051)
is detected in the initial UVOT exposures.

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             1740         1890          147         16.25 +/- 0.03
v                 1897         1917           20         16.07 +/- 0.14
b                 1995         2013           18         16.58 +/- 0.10
u                 1970         1990           20         15.93 +/- 0.10
w1                1946         1966           20         16.20 +/- 0.17
m2                1921         2114           39         16.60 +/- 0.18
w2                2045         2065           19         16.37 +/- 0.19

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.29 in the direction of the burst
(Schlegel et al. 1998).