GCN Circular 7122
Subject
GRB 071122: ROTSE-III Optical Limits
Date
2007-11-22T02:00:31Z (16 years ago)
From
Eli Rykoff at UCSB <erykoff@physics.ucsb.edu>
E.S. Rykoff (UCSB), W. Rujopakarn (Steward), B. E. Schaefer (Louisiana
State), T.A. McKay (U Mich), H. Swan (U Mich), report on behalf of the
ROTSE collaboration:
ROTSE-IIIb, located at McDonald Observatory, Texas, responded to GRB
071122 (Swift trigger 297114; Stamatikos et al., GCN 7121), producing
images beginning 8.5 s after the GCN notice time. An automated response
took the first image at 01:24:51.5 UT, 85.9 s after the burst, under
fair conditions. These observations were affected by proximity to the
full moon. We took 10 5-sec, and 30 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. Individual images have limiting
magnitudes ranging from 15.7-16.8; we set the following specific limits.
start UT end UT t_exp(s) mlim t_start-tGRB(s) Coadd?
--------------------------------------------------------------------
01:24:51.5 01:24:56.5 5 15.8 85.9 N
01:24:51.4 01:25:58.5 67 17.3 85.8 Y
01:26:12.0 01:30:54.8 282 17.8 166.4 Y