Reduced nuclear helicity amplitudes: Deuteron disintegration

The reduced nuclear helicity amplitude (RNHA) method is applied to deuteron photodisintegration and electrodisintegration. This extends the original reduced nuclear amplitude idea of Brodsky and Chertok to helicity amplitudes and allows the construction of polarization observables. In particular, we find the Σ asymmetry to be approximately -0.06, much closer to experiment than the value of -1 originally obtained in perturbative QCD.