2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/207495Events in PbarP collisions at sqrt(s)=1.8 TeV with total transverse energy exceeding 500 GeV are used to set limits on quark substructure. The data are consistent with next-to-leading order QCD calculations. We set a lower limit of 2.0 TeV at 95% confidence on the energy scale Lambda_LL for compositeness in quarks, assuming a model with a left-left isoscalar contact interaction term. The limits on Lambda_LL are found to be insensitive to the sign of the interference term in the Lagrangian.Submitted to Phys. Rev. D, Rapid Communications. 11 pages, 2 figuresHigh Energy Physics - Experimenttext