Dynamical friction-driven orbital circularisation in rotating discs: a
  semi-analytical description
  We present and validate a novel semi-analytical approach to study the effect
of dynamical friction on the orbits of massive perturbers in rotating stellar
discs. We find that dynamical friction efficiently circularises the orbit of
co-rotating perturbers, while it constantly increases the eccentricity of
counter-rotating ones until their angular momenta reverse, then once again
promoting circularisation. Such "drag toward circular corotation" could shape
the distribution of orientations of kinematically decoupled cores in disc
galaxies, naturally leading to the observed larger fraction of co-rotating
cores.
