GCN Circular 8807
Subject
GRB 090113: ROTSE-III Optical Limits
Date
2009-01-13T23:23:49Z (15 years ago)
From
Heather Swan at U.of Michigan/ROTSE <hflewell@umich.edu>
H. Swan (U Mich), E.S. Rykoff (UCSB), T. Guver (U Arizona), T.A. McKay
(U Mich), F. Yuan (U Mich), B. E. Schaefer (Louisiana State), R. Quimby
(Caltech), report on behalf of the ROTSE collaboration:
ROTSE-IIId, located at the Turkish National Observatory at Bakirlitepe,
Turkey, responded to GRB 090113 (Swift trigger 339852; H. A. Krimm, GCN
8804), producing images beginning 6.4 s after the GCN notice time. An
automated response took the first image at 18:49:02.4 UT, 503.2 s after
the burst, under windy conditions. We took 10 5-sec, 10 20-sec and 30
60-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, for both single images and coadding into
sets of 10; the field is not crowded. 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 t_start-tGRB(s) Coadd?
--------------------------------------------------------------------
18:49:02.5 18:51:08.2 125 16.6 503.3 Y
18:51:16.6 18:55:52.3 275 17.3 637.4 Y
18:60:45.7 19:05:21.5 275 17.3 1206.5 Y