2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/77119The ``symplectic cut'' construction [Lerman] produces two symplectic orbifolds $C_-$ and $C_+$ from a symplectic manifold $M$ with a Hamiltonian circle action. We compute the rational cohomology ring of $C_+$ in terms of those of $M$ and $C_-$.8 pages, no pictures, LaTeX twice. Fixed some indices (that don't affect the result), and added a comment on alternate methods of calculationSymplectic GeometryAlgebraic GeometryAlgebraic TopologyDifferential Geometrytext