  Most massive stars are found in the center of dense clusters, and have a
companion fraction much higher than their lower mass siblings; the massive
stars of the Trapezium core in Orion have ~ 1.5 companions each. This high
multiplicity could be a consequence of formation via a capture scenario, or it
could be due to fragmentation of the cores that form the massive stars. During
stellar formation circumstellar disks appear to be nearly ubiquitous. Their
large radii compared to stellar sizes increase the interaction radius
significantly, suggesting that disk interactions with neighboring stars could
assist in capturing binary companions. This mechanism has been studied for
stars of approximately solar mass and found to be inefficient. In this paper we
present simulations of interactions between a 22 Msun star-disk system and less
massive impactors, to study the disk-assisted capture formation of binaries in
a regime suited to massive stars. The formation of binaries by capture is found
to be much more efficient for massive capturers. We discuss the effects of a
mass dependent velocity dispersion and mass segregation on the capture rates,
and consider the long term survival of the resultant binaries in a dense
cluster.
