  The semimajor axis distribution of giant exoplanets appears to have a pileup
near 1 AU. Photoevaporation opens a gap in the inner few AU of gaseous disks
before dissipating them. Here we investigate whether photoevaporation can
significantly affect the final distribution of giant planets by modifying gas
surface density and hence Type II migration rates near the photoevaporation
gap. We first use an analytic disk model to demonstrate that newly-formed giant
planets have a long migration epoch before photoevaporation can significantly
alter their migration rates. Next we present new 2-D hydrodynamic simulations
of planets migrating in photoevaporating disks, each paired with a control
simulation of migration in an otherwise identical disk without
photoevaporation. We show that in disks with surface densities near the minimum
threshold for forming giant planets, photoevaporation alters the final
semimajor axis of a migrating gas giant by at most 5% over the course of 0.1
Myr of migration. Once the disk mass is low enough for photoevaporation to
carve a sharp gap, migration has almost completely stalled due to the low
surface density of gas at the Lindblad resonances. We find that
photoevaporation modifies migration rates so little that it is unlikely to
leave a significant signature on the distribution of giant exoplanets.
