TITLE:   GCN CIRCULAR
NUMBER:  8332
SUBJECT: GRB 081007, SMARTS optical/IR afterglow observations
DATE:    08/10/07 06:58:55 GMT
FROM:    Bethany Cobb at Yale U  <cobb@astro.yale.edu>

B. E. Cobb (UC Berkeley) reports:

Using the ANDICAM instrument on the 1.3m telescope at CTIO, we
obtained optical/IR imaging of the error region of GRB 081007
(GCN 8330, Baumgartner et al.), starting 23 minutes post-burst
in BVRIJHK.

In the R-band, the GRB afterglow (GCN 8330, Baumgartner et al.
& GCN 8331, Covino et al.) appears to fade by approximately 0.6 magnitudes
between 23 minutes and 56 minutes post-burst, indicating
a decay rate of alpha = -0.6 (where afterglow flux is proportional to
t^alpha).

Observations of this burst are continuing.