  The in-medium properties of a hyperon-nucleon potential, derived within
chiral effective field theory and fitted to Lambda-N and Sigma-N scattering
data, are investigated. Results for the single-particle potentials of the
Lambda and Sigma hyperons in nuclear matter are reported, based on a
conventional first-order Brueckner calculation. The Sigma-nucleus potential is
found to be repulsive, in agreement with phenomenological information. A weak
Lambda-nucleus spin-orbit interaction can be achieved by an appropriate
adjustment of a low-energy constant corresponding to an antisymmetric Lambda-N
-- Sigma-N spin-orbit interaction that arises at next-to-leading order in the
effective field theory approach.
