[vsnet-grb-info 5042] GRB 070809: Swift/UVOT Corrected Photometry

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  6751
SUBJECT: GRB 070809:  Swift/UVOT Corrected Photometry
DATE:    07/08/10 20:54:59 GMT
FROM:    Margaret Chester at PSU  <chester at astro.psu.edu>

M.M. Chester (PSU) and F.E. Marshall (NASA/GSFC) report on behalf of the
Swift UVOT team:

We have identified an additional exposure of GRB 070809 made by the 
Swift/UVOT that covers the XRT error circle, and can now provide an
optical upper limit at a much earlier time, 74 seconds after the BAT
trigger.  In addition, an error in the photometry analysis previously 
reported (Chester et al., GCN Circ. 6744) has been identified, and 
corrected upper limits are reported below.

Filter   Tstart   Tstop    Exp     Magnitude
           (s)      (s)     (s)    (3-sigma UL)
v (FC)     74      474    394       19.1
v        6344    18560   1251       20.2
b        5932    24593    614       20.4
u        5727    24363   1911       20.6
uvw1     5523    23449   2164       20.6
uvm2     5317    19316   2018       21.0
uvw2     6139    17646   1279       20.6