TITLE: GCN CIRCULAR NUMBER: 11095 SUBJECT: Swift/UVOT observations of GRB100814A DATE: 10/08/14 15:26:23 GMT FROM: Patricia Schady at MPE/Swift M. De Pasquale (MSSL-UCL) and C.J. Saxton (MSSL-UCL) report on the behalf of the Swift UVOT team: ��The Swift/UVOT began settled observations of the field of GRB 100814A 153 s after the BAT trigger ��(Beardmore et al. 2010, GCN Circ. 11087) with a finding chart in the u filter. We detect the optical afterglow in all filters except uvw2. The refined UVOT position is ��RA ��(J2000) = 01h 29m 53.61s = 22.47338 ��Dec (J2000) = -17d 59m 43.6s = -17.99545 with an estimated uncertainty of 0.6 arcsec (radius, 90% confidence, statistical + systematic). This is about 1.5 arcsec north of the UVOT-enhanced XRT position (Beardmore et al. 2010, GCN Circ. 11092). ��Preliminary magnitudes, and 3-sigma upper limits for detecting a source in the finding charts and in co-added images are Filter �� �� ��T_start �� T_stop �� ��Exp(s) �� �� ��Mag �� Err --------------------------------------------------------------------- �� ��u (fc) �� �� ��153 �� �� ��403 �� �� �� 246 �� �� 16.80 0.06 �� ��v �� �� �� �� �� 458 �� ���� 627 �� �� �� ��39 �� �� ��17.91 0.32 �� ��b �� �� �� �� �� 408 �� ���� 721 �� �� �� ��53 �� �� ��21.22 0.20 �� ��u �� �� �� �� �� 153 �� ���� 701 �� �� ��285 �� �� ��16.84 0.06 ��uvw1 �� �� �� ��507 �� �� ��676 �� �� �� ��39 �� �� �� 17.33 0.20 ��uvm2 �� �� �� 483 �� �� 651 �� �� �� 39 �� �� ��17.86 0.31 ��uvw2 �� �� �� ��434 �� �� 602 �� �� �� 39 �� ��>18.52 ��3-sigma UL ��white �� �� ��3858 �� �� 4211 �� �� �� 344 �� �� ��18.63 0.07 ----------------------------------------------------------- ��The quoted magnitudes and upper limits have not been corrected for the expected Galactic extinction along the line of sight corresponding to a reddening of E_{B-V} = 0.02 mag (Schlegel, et al., 1998, ApJS, 500, 525). ��All photometry is on the UVOT photometry system described in Poole et al. (2008, MNRAS, 383, 627).