2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/60411We relate the brace products of a fibration with section to the differentials in its serre spectral sequence. In the particular case of free loop fibrations, we establish a link between these differentials and browder operations in the fiber. Applications and several calculations (for the particular case of spheres and wedges of spheres) are given.23pages (to appear in Proc. London Math. Soc.)Algebraic Topology55P35, 55Q15, 55R05, 55R20text