2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/149020We consider the neutralino mass matrix in a supersymmetric theory based on SU(2) $\times$ U(1) gauge group with arbitrary number of singlet, doublet and triplet Higgs superfields. We derive an upper bound on the mass of the lightest neutralino, and a lower bound on the mass of the heaviest neutralino, in such a theory. Assuming grand unification of the gauge couplings, the upper bound on the mass of the lightest neutralino can be expressed in terms of the gluino mass. For a gluino mass of 200 GeV, the tree level upper bound on the mass of the lightest neutralino is 92 GeV, which increases to 166.5 GeV for a 1 TeV gluino. We also discuss the effect of dominant one-loop radiative corrections on these bounds.15 pages, latex, no figures, minor typographical correctionsHigh Energy Physics - Phenomenologytext