  O- and B-type stars are often found in binary systems, but the low binary
mass-ratio regime is relatively unexplored due to observational difficulties.
Binary systems with low mass-ratios may have formed through fragmentation of
the circumstellar disk rather than molecular cloud core fragmen- tation. We
describe a new technique sensitive to G- and K-type companions to early B
stars, a mass-ratio of roughly 0.1, using high-resolution, high signal-to-noise
spectra. We apply this technique to a sample of archived VLT/CRIRES
observations of nearby B-stars in the CO bandhead near 2300 nm. While there are
no unambiguous binary detections in our sample, we identify HIP 92855 and HIP
26713 as binary candidates warranting follow-up observations. We use our
non-detections to determine upper limits to the frequency of FGK stars orbiting
early B-type primaries.
