Benchmark calculation of n-3H and p-3He scattering

TL;DR

This paper compares three computational methods for calculating elastic phase-shifts in n-3H and p-3He scattering using various realistic nucleon-nucleon interactions, and evaluates their agreement with experimental data.

Contribution

It provides a comprehensive benchmark comparison of three different theoretical approaches for four-nucleon scattering calculations with multiple realistic interactions.

Findings

Good agreement among the three methods for phase-shifts.

Theoretical models underpredict p-3He analyzing power.

Comparison highlights strengths and limitations of current models.

Abstract

The n-3H and p-3He elastic phase-shifts below the trinucleon disintegration thresholds are calculated by solving the 4-nucleon problem with three different realistic nucleon-nucleon interactions (the I-N3LO model by Entem and Machleidt, the Argonne v18 potential model, and a low-k model derived from the CD-Bonn potential). Three different methods -- Alt, Grassberger and Sandhas, Hyperspherical Harmonics, and Faddeev-Yakubovsky -- have been used and their respective results are compared. For both n-3H and p-3He we observe a rather good agreement between the three different theoretical methods. We also compare the theoretical predictions with the available experimental data, confirming the large underprediction of the p-3He analyzing power.