Meson-exchange currents and final-state interactions in quasielastic electron scattering at high momentum transfers

TL;DR

This paper investigates how meson-exchange currents and final-state interactions influence the quasielastic electron scattering response at high momentum transfers, highlighting the importance of relativistic effects and specific potential models.

Contribution

It introduces a semi-relativistic shell model incorporating relativistic kinematics and Dirac-based potentials to analyze MEC and FSI effects at high momentum transfers.

Findings

FSI significantly enhances MEC in the high-energy tail at q ≥ 1 GeV/c

The combined MEC and FSI effects depend on the FSI model used

Relativistic effects are crucial for accurate response function calculations

Abstract

The effects of meson-exchange currents (MEC) are computed for the one-particle one-hole transverse response function for finite nuclei at high momentum transfers $q$ in the region of the quasielastic peak. A semi-relativistic shell model is used for the one-particle-emission $(e,e')$ reaction. Relativistic effects are included using relativistic kinematics, performing a semi-relativistic expansion of the current operators and using the Dirac-equation-based (DEB) form of the relativistic mean field potential for the final states. It is found that final-state interactions (FSI) produce an important enhancement of the MEC in the high-energy tail of the response function for $q\geq 1$ GeV/c. The combined effect of MEC and FSI goes away when other models of the FSI, not based on the DEB potential, are employed.