GCN Circular 13969
Subject
GRB 121117A: ROTSE-III Optical Limits
Date
2012-11-17T13:05:41Z (11 years ago)
From
Weikang Zheng at U.of Michigan <zwk@umich.edu>
W. Zheng (U Mich), report on behalf of the ROTSE collaboration:
ROTSE-IIIb, located at McDonald Observatory, Texas, responded to GRB 121117A
(Swift trigger 538696; Cummings et al., GCN 13967), producing images
beginning 9.1 s after the GCN notice time. An automated response took the
first image at 08:51:21.1 UT, 24.1 s after the burst, under fair conditions.
We took 10 5-sec, 10 20-sec and 20 60-sec exposures. 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. Individual images have limiting magnitudes
ranging from 14.9-16.4; we set the following specific limits.
start UT end UT t_exp(s) mlim Coadd?
---------------------------------------------------
08:50:57.0 08:55:57.0 5 15.0 N
08:51:32.0 08:51:37.0 5 15.0 N
08:51:43.0 08:51:48.0 5 15.4 N
08:51:55.0 08:52:00.0 5 15.2 N
08:52:07.0 08:52:12.0 5 15.2 N
08:50:57.0 08:53:04.0 50 16.8 Y
08:53:18.0 08:57:59.0 200 17.2 Y