2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/193122We compute the QCD form factor resumming threshold logarithms in B --> X_c + l + nu_l decays to next-to-leading logarithmic approximation. We present an interpolation formula including soft as well as collinear effects softened by the non-vanishing charm mass.24 pages, no figuresHigh Energy Physics - Phenomenologytext