An application of the reduction method to Sutherland type many-body systems

We study Hamiltonian reductions of the free geodesic motion on a non-compact simple Lie group using as reduction group the direct product of a maximal compact subgroup and the fixed point subgroup of an arbitrary involution commuting with the Cartan involution. In general, we describe the reduced system that arises upon restriction to a dense open submanifold and interpret it as a spin Sutherland system. This dense open part yields the full reduced system in important special examples without spin degrees of freedom, which include the BC(n) Sutherland system built on 3 arbitrary couplings for m<n positively charged and (n-m) negatively charged particles moving on the half-line.