GCN Circular 10689
Subject
GRB100425A: Swift/UVOT Upper Limits
Event
Date
2010-04-25T18:00:55Z (16 years ago)
From
Samantha Oates at MSSL <sro@mssl.ucl.ac.uk>
S. R. Oates (MSSL-UCL) and D. Grupe (PSU) report on behalf of the
Swift/UVOT team:
The Swift/UVOT began settled observations of the field of
GRB 100425A 88s after the BAT trigger (Grupe et al., GCN 10673).
We do not detect a new source at the enhanced Swift XRT position
(Goad et al. GCN 10686) and at the location of source B detected
by the VLT telescope (Malesani et al. GCN 10680) and GROND
telescope (Olivares et al. GCN 10683). Photometry is complicated
by the prescence of the VLT source A within the source aperture.
The 3-sigma upper limits for the finding chart exposures (FC)
and summed images are:
Filter T_start T_stop Exp(s) Mag (3-sigma upper limit)
-------------------------------------------------------------
white (FC) 88 238 147 >19.37
white 88 5778 513 >19.59
u (FC) 301 551 246 >18.92
u 301 6796 650 >19.08
v 631 11961 1317 >19.76
b 556 5573 236 >19.71
uvw1 680 6600 432 >19.44
uvm2 4757 12580 997 >20.87
uvw2 606 11048 1318 >21.26
-------------------------------------------------------------
The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight of E_(B-V) = 0.15 mag.
All photometry is on the UVOT photometric system described in Poole et
al. (2008, MNRAS, 383, 627).