TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  4737
SUBJECT: GRB 060211: ROTSE-III Optical Limits
DATE:    06/02/11 10:43:25 GMT
FROM:    Wiphu Rujopakarn at U Michigan/ROTSE  <wiphu@umich.edu>

W. Rujopakarn (U Mich), E.S. Rykoff (U Mich), B. E. Schaefer (Louisiana 
State), F. Yuan (U Mich), S.A. Yost (U Mich), report on behalf of the 
ROTSE collaboration:

ROTSE-IIIa, located at Siding Spring Observatory, Australia, responded 
to GRB 060211 (Hurkett et al., GCN 4736), producing images beginning 
6.2 s after the GCN notice time. An automated response took the first 
image at 09:41:38.2 UT, 147.2 s after the burst, under twilight 
conditions. We took 10 5-sec, and 100 20-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 error circle, for both single images and coadding into sets of 
10. Individual images have limiting magnitudes ranging from 14.0-16.2; 
we set the following specific limits.

start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
--------------------------------------------------------------------
09:41:38.2   09:41:43.2         5     14.3          147.2       N
09:41:38.2   09:43:51.7       133     15.7          147.2       Y
09:44:00.9   09:48:44.2       283     16.1          289.9       Y