GCN Circular 3022

S.A. Yost, D.A. Smith, and E.S. Rykoff report on behalf of the ROTSE
collaboration:

ROTSE3B, located at McDonald Observatory, Texas, responded to GRB050215B
(Swift#0106107) under fair conditions (low elevation). An automatic
response (interrupting the sequence for 050215A) resulted in a sequence of
60+ images beginning 8 sec after the trigger. The first image was taken at
02:35:19.0, 97 sec after the burst. We took 10 5 sec, 10 20 sec, and 40+
60 sec exposures. The images are unfiltered and were calibrated relative
to USNO A2.0.

Individual images have limiting magnitudes from 16-17.7 mag. Comparison to
the DSS reveals no new sources within the 3-sigma error circle to a
limiting magnitude of 17.8-18.8 for coadded sets of 10 images between 100
sec and 50 min post-burst

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