Threshold 3He and 3H Transverse Electron Scattering Response Functions

TL;DR

This paper calculates the threshold transverse response functions for helium-3 and tritium using advanced nuclear potentials and currents, compares with experimental data, and discusses the contributions of meson exchange currents.

Contribution

It provides a comprehensive calculation of the response functions including final state interactions and meson exchange currents, with comparisons to data and other models.

Findings

Strong MEC contributions are confirmed by data at higher momentum transfers.

Good overall agreement with experimental data, with some discrepancies.

Method demonstrates convergence and consistency with other theoretical approaches.

Abstract

The threshold transverse response functions R_T(q,omega) for 3He and 3H are calculated using the AV18 nucleon-nucleon potential, the UrbanaIX three-body force, and the Coulomb potential. Final states are completely taken into account via the Lorentz integral transform technique. Consistent two-body pi- and rho-meson exchange currents as deduced using the Arenh\"ovel-Schwamb technique are included. The convergence of the method is shown and a comparison of the corresponding MEC contribution is made to that of a consistent MEC for the meson theoretical r-space BonnA potential. The response R_T is calculated in the threshold region at q=174, 324, and 487 MeV/c and compared with available data. The strong MEC contributions in the threshold region are nicely confirmed by the data at q=324 and 487 MeV/c although some differences between theoretical and experimental results remain. A comparison is also made with other calculations, where the same theoretical input is used. The agreement is generally rather good, but leaves also some space for further improvement.