2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/161799A study is made of the power-law tail effect in the quantum particle distribution over momentum on the nuclear fusion reactions. Our results do not support the idea of averaging the fusion reaction cross-section over the momentum distribution postulated and used in many publications.8 pages, LaTeX; typos addedAstrophysicstext