Optical stochastic cooling (OSC) holds significant promise for cooling of charged particle beams to enhance
the luminosity of high energy colliders. This paper describes the conceptual design and requirements for an
interferometer to be built for an OSC demonstration experiment with stored electrons at the MIT-Bates South
Hall Ring. The paper will present an overview of the optical and charged particle beamlines, the intensity
detection system and the phase stabilizing feedback loop.