2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/226016We construct a relative Chow-Kunneth decomposition for a conic bundle over a surface such that the middle projector gives the Prym variety of the associated double covering of the discriminant of the conic bundle. This gives a refinement (up to an isogeny) of Beauville's theorem on the relation between the intermediate Jacobian of the conic bundle and the Prym variety of the double covering.19 pages, to appear in IMRNAlgebraic Geometry14C25text