2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/39426We examine pair mass dependence near threshold as a means to measure the spin of the top quark in hadron collisions, and we discuss the possibility that a top squark signal could be hidden among the top events.9 pages, RevTeX, 3 figures. Contribution to the Thinkshop on Top-Quark Physics for the Tevatron Run II, Fermilab, October 16 - 18, 1999High Energy Physics - Phenomenologytext