  We surveyed thirteen very low mass (VLM; M < 0.2 M_sun) objects in the Taurus
star-forming region using near-infrared diffraction-limited imaging techniques
on the W.M. Keck I 10 m telescope. Of these thirteen, five were found to be
binary, with separations ranging from 0.04" to 0.6" and flux ratios from 1.4 to
3.7. In all cases, the companions are likely to be physically associated with
the primaries (probability > 4-sigma). Using the theoretical models of Baraffe
et al. (1998), we find that all five new companions, as well as one of the
primaries, are likely brown dwarfs. The discovery of these systems therefore
increases the total number of known, young VLM binaries by ~50%. These new
systems, along with other young VLM binaries from the literature, have
properties that differ significantly from older field VLM binaries in that the
young systems have wider separations and lower mass ratios, supporting the idea
that VLM binaries undergo significant dynamical evolution ~5 - 10 Myr after
their formation. The range of separations of these binaries, four of which are
over 30 AU, argues against the ejection scenario of brown dwarf formation.
While several of the young, VLM binaries discovered in this study have lower
binding energies than the previously suggested minimum for VLM binaries, the
apparent minimum is still significantly higher than that found among higher
mass binaries. We suggest that this discrepancy may be due to the small mass of
a VLM binary relative to the average perturbing star, leading to more
substantial changes in their binding energy over time.
