TITLE:   GCN CIRCULAR
NUMBER:  15850
SUBJECT: GRB140215A: Continued Discovery Channel Telescope Observations
DATE:    14/02/16 18:08:36 GMT
FROM:    Vicki Toy at UMD  <vtoy@astro.umd.edu>

V. Toy (UMD), S.B. Cenko (NASA-GSFC), A. Kutyrev (NASA-GSFC), J. Capone
(UMD), E. Troja (NASA-GSFC), A. Cucchiara (NASA-GSFC), S. Veilleux (UMD),
and S. Gezari (UMD) report on behalf of a larger collaboration:

We re-observed the bright optical afterglow of GRB140215A (Swift trigger
586680, Markwardt et al., GCN 15837, Cenko et al., GCN 15840) with the
Large Monolithic Imager (LMI) on the 4.3m Discovery Channel Telescope (DCT)
at Happy Jack, AZ from 2014/02/16 2:55 to 2014/02/16 4:05 UTC (0.95-1.0
days after the Swift-BAT trigger) in the g',r',i', and z' filters.

Compared with our previous observations, the afterglow continues to follow
an unbroken power law with decay index of alpha=-1.20 in all filters
(Perley et al., GCN 15844, and Elenin et al., GCN 15846), consistent with
the simultaneous temporal decay observed in the X-rays (Page et al., GCN
15845).  Specifically we measure r' = 21.6 mag (AB) at a time of 23.5 hr
after the trigger, calibrating relative to USNO-B1.

We thank the entire staff of the Discovery Channel Telescope for assistance
with these observations.