GCN Circular 6404
Subject
GRB 070509: Swift/UVOT Upper Limits
Event
Date
2007-05-10T16:00:38Z (19 years ago)
From
Stephen Holland at USRA/NASA/GSFC/SSC <sholland@milkyway.gsfc.nasa.gov>
S. T. Holland (CRESST/GSFC/USRA) and L. Vetere (PSU)
report on the behalf of the Swift UVOT team:
The Swift/UVOT observed the field of GRB 070509 starting 73 s
after the BAT trigger (Vetere et al. 2007, GCN Circ. 6394). We do
not find any source, in any of the UVOT observations, inside the
refined XRT error circle (Vetere et al., 2007 GCN Circ. 6400).
The 3-sigma upper limits for detecting a source anywhere inside
the refined XRT error circle in the co-added frames are:
Filter T_start T_stop Exp(s) Mag (3-sigma upper limit)
-----------------------------------------------------------------
V 179 6074 1003 20.6
B 657 1468 39 18.6
U 633 1443 58 18.4
UVW1 609 1419 58 18.0
UVM2 584 6085 65 17.5
UVW2 686 5869 236 19.3
White 73 1482 225 21.1
-----------------------------------------------------------------
The values quoted above are not corrected for the expected Galactic
extinction corresponding to a reddening of E_{B-V} = 0.14 mag towards
the direction of the burst (Schlegel et al. 1998).