TITLE: GCN CIRCULAR NUMBER: 8591 SUBJECT: Swift Trigger 335971: Swift/UVOT Observations DATE: 08/12/01 23:06:09 GMT FROM: Frank Marshall at GSFC F.E. Marshall (NASA/GSFC) and J. Mao (INAF-OAB) report on behalf of the Swift/UVOT team: The Swift/UVOT observed the field of Swift trigger 335971 on Nov. 29, 2008, starting 141 s after the BAT trigger (Mao et al., GCN Circ. 8582). Ground analysis of the BAT data indicates that this trigger was probably not due to a real source (Cummings and Mao, GCN Circ. 8583). No new source is seen inside the BAT error circle (Cummings and Mao, GCN Circ. 8583) in any of the individual or summed UVOT exposures. The 3-sigma upper limits in the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) are: Filter T_start(s) T_stop(s) Exp(s) Mag white 141 291 147 >20.6 v 376 742 58 >18.6 b 474 840 58 >19.5 u 450 815 58 >19.4 uvw1 425 790 58 >19.0 uvm2 401 766 58 >18.8 uvw2 351 717 58 >19.0 The values quoted above are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.10 in the direction of the burst (Schlegel et al. 1998).