Meson-exchange currents in quasielastic electron scattering in a generalized superscaling approach

TL;DR

This paper introduces a model incorporating meson-exchange currents into quasielastic electron scattering within a superscaling framework, allowing for consistent analysis of two-body current effects on response functions and cross sections.

Contribution

The model uniquely combines one- and two-body currents in a superscaling formalism, enabling the calculation of exchange current effects in regions previously inaccessible.

Findings

MEC deplete the quasielastic transverse response.

MEC do not significantly alter the scaling behavior of electron scattering data.

The model accounts for MEC effects on the inclusive cross section.

Abstract

We present a model that incorporates the effect of two-body currents in quasielastic electron-nucleus scattering within the framework of a consistent superscaling formalism. This is achieved by defining an averaged single-nucleon hadronic tensor based on the 1p1h matrix element of the one-body current plus meson-exchange currents (MEC). The consistent treatment of one- and two-body currents in our model enables the calculation of exchange current effects in the kinematical region where the Fermi gas response is zero, but not the scaling function. The effect of MEC is consistently taken into account when extracting the phenomenological scaling function from electron scattering data. With this model, we investigate the effect of MEC on the response functions taking into account the effective mass of the nucleon, and examine the consequences it has on the inclusive $(e,e')$ cross section. We find that 1p1h MEC deplete the quasielastic transverse response, while they not alter significantly the scaling behavior of (e,e') data.