2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/196742We use the Type Ia Supernova gold sample data of Riess {\it et al} in order to constrain three models of dark energy. We study the Cardassian model, the Dvali-Turner gravity modified model and the generalized Chaplygin gas model of dark energy - dark matter unification. In our best fit analysis for these three dark energy proposals we consider flat model and the non-flat model priors. We also discuss the degeneracy of the models with the XCDM model through the computation of the so-called jerk parameter.Revtex4, 11 pages, 6 sets of figures, 3 tables. Version published at Physical Review DAstrophysicstext