Relativistic Effects in Exclusive pd Breakup Scattering at Intermediate Energies

TL;DR

This paper develops a relativistic three-nucleon scattering model using the Faddeev equation in momentum space, demonstrating significant relativistic effects and good agreement with experimental data at intermediate energies.

Contribution

It formulates a relativistic Faddeev approach without partial wave decomposition, incorporating Poincaré invariance for accurate three-nucleon scattering predictions.

Findings

Relativistic effects significantly impact cross sections.

Good agreement with experimental data at 508 MeV.

Multiple scattering series convergence varies by configuration.

Abstract

The relativistic Faddeev equation for three-nucleon scattering is formulated in momentum space and directly solved in terms of momentum vectors without employing a partial wave decomposition. Relativistic invariance is achieved by constructing a dynamical unitary representation of the Poincar\'e group on the three-nucleon Hilbert space. The exclusive breakup reaction at 508 MeV is calculated based on a Malfliet-Tjon type of two-body interaction and the cross sections are compared to measured cross sections at this energy. We find that the magnitude of the relativistic effects can be quite large and depends on the configurations considered. In spite of the simple nature of the model interaction, the experimental cross sections are in surprisingly good agreement with the predictions of the relativistic calculations. We also find that although for specific configurations the multiple scattering series converges rapidly, this is in general not the case.