Young intermediate-mass stars have become high-priority targets for
direct-imaging planet searches following the recent discoveries of planets
orbiting e.g. HR 8799 and Beta Pictoris. Close stellar companions to these
stars can affect the formation and orbital evolution of any planets, and so a
census of the multiplicity properties of nearby intermediate mass stars is
needed. Additionally, the multiplicity can help constrain the important binary
star formation physics. We report initial results from a spectroscopic survey
of 400 nearby A- and B-type stars. We search for companions by
cross-correlating high resolution and high signal-to-noise ratio echelle
spectra of the targets stars against model spectra for F- to M-type stars. We
have so far found 18 new candidate companions, and have detected the spectral
lines of the secondary in 4 known spectroscopic binary systems. We present the
distribution of mass-ratios for close companions, and find that it differs from
the distribution for wide (a<100 AU) intermediate-mass binaries, which may
indicate a different formation mechanism for the two populations.Comment: Submitted as part of the 18th Cambridge Workshop on Cool Stars,
Stellar Systems, and the Sun Proceedings of Lowell Observatory (9-13 June
2014
