GCN Circular 8730
Subject
GRB 081226: ROTSE-III Optical Limits
Event
Date
2008-12-26T01:32:34Z (17 years ago)
From
Brad Schaefer at LSU <schaefer@grb.phys.lsu.edu>
B. E. Schaefer (Louisiana State), E.S. Rykoff (UCSB), F. Yuan (U Mich),
report on behalf of the ROTSE collaboration:
ROTSE-IIIc, located at the H.E.S.S. site at Mt. Gamsberg, Namibia,
responded to GRB 081226 (Swift trigger 338177; Godet, GCN 8729), producing
images beginning 8.8 s after the GCN notice time. An automated response
took the first image at 01:04:02.8 UT, 25.4 s after the burst, under
excellent conditions. We took 10 5-sec, 20 20-sec exposures. These
unfiltered images are calibrated relative to USNO A2.0 (R). Imaging is on
going.
Comparison to the DSS (second epoch) reveals no new sources within the
3-sigma Swift/BAT error circle or the XRT error circle, for both single
images and coadding into sets of 10; the field is not crowded. Individual
images have limiting magnitudes ranging from 16.8-17.4; we set the
following specific limits.
start UT end UT t_exp(s) mlim t_start-tGRB(s) Coadd?
--------------------------------------------------------------------
01:04:02.8 01:04:07.8 5 17.0 25.4 N
01:04:02.9 01:05:19.0 76 17.8 25.5 Y