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GCN Circular 6744

GRB 070809: Swift/UVOT Upper Limits
2007-08-10T16:10:59Z (17 years ago)
Margaret Chester at PSU <>
M.M. Chester (PSU) and F.E. Marshall (NASA/GSFC) report on behalf
of the Swift UVOT team:

The Swift/UVOT observed the field of GRB 070809 (Marshall et al., GCN
Circ. 6728) beginning 2007-08-09, 20:50:54, 5317 seconds after the BAT

We do not find any new source in any of the UVOT observations inside the
Swift/XRT error circle (RA,DEC(J2000)= 203.7708, -22.1408).

The 3-sigma upper limits for detecting a source inside the XRT error
circle in the co-added frames are:

Filter   Tstart   Tstop    Exp     Magnitude
            (s)     (s)     (s)    (3-sigma UL)
v        6344     18560   1251       20.8
b        5932     24593    614       21.3
u        5727     24363   1911       21.7
uvw1     5523     23449   2164       21.7
uvm2     5317     19316   2018       21.7
uvw2     6139     17646   1279       21.6

The values quoted above are not corrected for the expected Galactic
extinction corresponding to a reddening of E_{B-V} = 0.09 mag in the
direction of the burst (Schlegel et al. 1998).
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