GCN Circular 3540

James Rhoads reports on behalf of a larger collaboration:

We observed the afterglow of GRB 050607 with the 4m Mayall Telescope
of Kitt Peak National Observatory from UT 2005 June 8 10:33 to 11:05.
We obtained three I band exposures with total integration time
of 26 minutes.  The GRB counterpart is weakly detected in the sum
of the three images, with a statistical error around 0.2 to 0.25
magnitudes.

Relative photometry with respect to a nearby field star
shows that the transient has faded by 2.3 +- 0.2 magnitudes
between t=640 seconds and t=92300 seconds post-trigger.

Based on a power law fit to the night 1 data (Rhoads, GCNC 3531),
with decay slope 0.5, we would expect a fading of 2.9 magnitudes
over the same period.   This suggests that host galaxy light may
be contributing detectably to our most recent flux measurement.
However, the statistical significance of this excess is low.
A single power law fit to the combined night one and night two
data has a time decay slope of 0.4 and nearly acceptable residuals.
If we exclude the first point (t=640 seconds) from the fit, on the
supposition that the physics dominating the afterglow changed
around 1e3 seconds, the decay slope in our other UT 050607 data
becomes 0.3 and the UT 050608 point lies precisely on this shallow,
extrapolated decay.

Additional data would help distinguish among these possibilities,
and further monitoring is encouraged.