GCN Circular 8962
Subject
GRB 090308: Swift/UVOT Upper Limits
Event
Date
2009-03-09T18:31:52Z (17 years ago)
From
Frank Marshall at GSFC <marshall@milkyway.gsfc.nasa.gov>
F.E. Marshall (NASA/GSFC) and P. Evans (U. Leicester)
report on behalf of the Swift/UVOT team:
The Swift/UVOT observed the field of GRB 0900308 starting 132 s after
the BAT trigger (Evans et al., GCN Circ. 8948). No optical afterglow
is detected in the initial UVOT exposures at the position
of the X-ray afterglow (Evans and Page, GCN Circ. 8956).
Three-sigma upper limits using the UVOT photometric system
(Poole et al. 2008, MNRAS, 383, 627) for the first finding chart (FC)
exposure and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white (FC) 132 282 147 >21.1
white 570 11390 1102 >22.2
v 620 17423 1101 >20.6
b 545 6455 382 >20.8
u 290 6281 639 >20.7
uvw1 669 6077 399 >20.6
uvm2 644 18019 798 >20.8
uvw2 595 12237 1044 >21.2
The values quoted above are not corrected for the Galactic extinction due
to the reddening of E(B-V) = 0.11 in the direction of the burst
(Schlegel et al. 1998).