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

GRB 160401: Swift/UVOT Upper Limits

***UBS*** (***INSTITUTION***) and ***BA*** (***BA INSTITUTION***)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 160401
42847 s after the INTEGRAL trigger (***Author*** et al., GCN Circ. ????).
No optical afterglow consistent with the INTEGRAL 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 initial exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white            43678        44209          522         >20.9
v                44509        45370          843         >19.5
u                42847        49071         1268         >20.1

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 1.13 in the direction of the burst
(Schlegel et al. 1998).