Action-angle duality between the C(n)-type hyperbolic Sutherland and the   rational Ruijsenaars-Schneider-van Diejen models
  In a symplectic reduction framework we construct action-angle systems of canonical coordinates for both the hyperbolic Sutherland and the rational Ruijsenaars-Schneider-van Diejen integrable models associated with the C(n) root system. The presented dual reduction picture permits us to establish the action-angle duality between these many-particle systems. 
B.G. Pusztai
math-ph hep-th math.MP math.SG