Hadronic electric dipole moments, the Weinberg operator, and light gluinos

We reexamine questions concerning the contribution of the three-gluon Weinberg operator to the electric dipole moment of the neutron, and provide several QCD sum-rule-based arguments that the result is smaller than--but nevertheless consistent with--estimates which invoke naive dimensional analysis. We also point out a regime of the minimal supersymmetric standard model parameter space with light gluinos for which this operator provides the dominant contribution to the neutron electric dipole moment due to enhancement via the dimension five color electric dipole moment of the gluino