2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/100016We consider an elliptic billiard whose shape slowly changes. During slow evolution of the billiard certain resonance conditions can be fulfilled. We study the phenomena of capture into a resonance and scattering on resonances which lead to the destruction of the adiabatic invariance in the system.Comments to ver. 1: This is an improved and corrected version of a paper recently published in Regular & Chaotic Dynamics. Comments to ver. 2: Compared to version 1, the figures were incorporated into manuscript file for convenience, no other changesChaotic Dynamicstext