2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/194339We consider the motion of test particles in a thick brane version of Randall-Sundrum type II model. It is known that gravity alone cannot explain the confinement of test particles in this kind of brane. In this paper we show that a stable confinement in a domain wall is possible by admitting a direct interaction between test particles and a scalar field. This interaction is implemented by a modification of the Lagrangian of the particle which is inspired by a Yukawa-type interaction between fermions and scalar fields.1 figure. Extended analysis to treat general thick branes RSII-type. Added referencesGeneral Relativity and Quantum Cosmologytext