Transverse electron scattering response function of 3He in the quasi-elastic peak region and beyond with Delta isobar degrees of freedom

TL;DR

This paper calculates the transverse electron scattering response function of helium-3, including Delta isobar currents, achieving improved agreement with experimental data and highlighting the importance of Delta degrees of freedom in nuclear reactions.

Contribution

The study introduces the inclusion of Delta isobar currents in the calculation of the 3He response function, enhancing the accuracy of theoretical predictions in the quasi-elastic peak region.

Findings

Delta-IC increases the peak height by about 5%.

Effects of three-nucleon forces largely cancel Delta-IC effects.

Delta-IC are significant in three-body break-up reactions.

Abstract

The 3He transverse electron scattering response function R_T(q,omega) is calculated in the quasi-elastic peak region and beyond for momentum transfers q = 500, 600 and 700 MeV/c. Distinct from our previous work for these kinematics where we included meson exchange currents and relativistic corrections we now additionally include Delta isobar currents (Delta-IC). The Delta-IC contribution increases the quasi-elastic peak height by about 5% and leads to an excellent agreement with experimental data in the whole peak region. In addition it is shown that effects due to the three-nucleon force largely cancel those due to the Delta-IC in the peak region. Finally, we have found that Delta-IC are important for three-body break-up reactions in the so-called dip region. This could explain why in a previous study of such a reaction, where Delta degrees of freedom were not included, no agreement between experimental and theoretical results could be obtained.