2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/46098We study the contribution of diffractive $Q \bar Q$ production to the $F_2^D$ proton structure function and the longitudinal double-spin asymmetry in polarized deep--inelastic $lp$ scattering. We show the strong dependence of the $F_2^D$ structure function and the $A_{ll}$ asymmetry on the quark--pomeron coupling structure.15 pages, latex, 5-Ps figuresHigh Energy Physics - Phenomenologytext