GCN Circular 7060
Subject
GRB 071112B: ROTSE-III Rapid Optical Limits
Date
2007-11-12T19:18:52Z (17 years ago)
From
Eli Rykoff at UCSB <erykoff@physics.ucsb.edu>
E.S. Rykoff (UCSB), F. Yuan (U Mich), W. Rujopakarn (Steward), report on
behalf of the ROTSE collaboration:
ROTSE-IIIc, located at the H.E.S.S. site at Mt. Gamsberg, Namibia,
responded to the short/hard GRB 071112B (Swift trigger 296503; Perri et
al., GCN 7058), producing images beginning 6.8 s after the GCN notice
time. An automated response took the first image at 18:23:55.8 UT, 24.3
s after the burst, under fair conditions. We took 10 5-sec, and 10
20-sec exposures before ROTSE-IIIc repointed at Swift trigger 296504
(GRB071111C). These unfiltered images are calibrated relative to USNO
A2.0 (R).
Comparison to the DSS (second epoch) reveals no new sources within the
3-sigma Swift/BAT error circle, for both single images and coadding into
sets of 10. Individual images have limiting magnitudes ranging from
15.3-16.3; we set the following specific limits.
start UT end UT t_exp(s) mlim t_start-tGRB(s) Coadd?
--------------------------------------------------------------------
18:23:55.8 18:24:00.8 5 15.5 24.3 N
18:23:55.8 18:25:45.1 109 16.6 24.3 Y
18:25:53.0 18:31:02.2 309 17.3 141.5 Y