Sensitivity of exclusive proton knockout spin observables to different Lorentz invariant representations of theNNinteraction

Abstract

Within the framework of the relativistic plane wave impulse approximation, we study the observable consequences of employing a complete Lorentz invariant representation of the NN scattering matrix in terms of 44 independent amplitudes, as opposed to the previously-employed, but ambiguous, five-term Lorentz invariant parametrization of the NN scattering matrix, for the prediction of complete sets of exclusive ( p, 2 p ) polarization transfer observables. Two kinematic conditions are considered, namely proton knockout from the 3s 1/2 state of 208 Pb at an incident energy of 202 MeV for coplanar scattering angles (28.0 • , −54.6 • ), as well as an incident energy of 392 MeV for the angle pair (32.5 • , −80.0 • ). The results indicate that certain spin observables are ideal for discriminating between the two representations.

Relativistic eikonal description ofA(p,pN)reactions

“…Tjon and Wallace [22] have shown that a complete expansion of the NN scattering matrix (commonly called the IA2 model) contains 44 independent invariant amplitudes. To date, the only calculations employing this general Lorentz invariant representation have been performed in the context of the relativistic plane wave impulse approximation (RPWIA), i.e., a model which ignores all IFSI mechanisms [23].…”