LAUSR

We investigate the evolutionary nexus between the morphology and internal kinematics of the central regions of collisional, rotating, multimass stellar systems, with special attention to the spatial characterization of the process of mass segregation. We report results from idealized, purely N-body simulations that show multimass, rotating, and spherical systems rapidly form an oblate, spheroidal massive core, unlike single-mass rotating, or multimass non-rotating configurations with otherwise identical initial properties, indicating that this evolution is a result of the interplay between the presence of a mass spectrum and angular momentum. This feature appears to be long-lasting, preserving itself for several relaxation times. The degree of flattening experienced by the systems is directly proportional to the initial degree of internal rotation. In addition, this morphological effect has a clear characterization in terms of orbital architecture, as it lowers the inclination of the orbits of massive stars. We offer an idealized dynamical interpretation that could explain the mechanism underpinning this effect and we highlight possible useful implications, from kinematic hysteresis to spatial distribution of dark remnants in dense stellar systems.