Charged-current quasielastic neutrino scattering from $^{12}$C in an extended superscaling model with two-nucleon emission

TL;DR

This paper develops an advanced superscaling model incorporating two-nucleon emission mechanisms and relativistic effects to accurately predict charged-current quasielastic neutrino scattering cross-sections on carbon-12, aligning with experimental data.

Contribution

It introduces an improved superscaling model that explicitly includes meson-exchange currents and two-particle-two-hole mechanisms with relativistic effective mass modifications.

Findings

Predicted neutrino and antineutrino cross sections match experimental measurements.

The model distinguishes between microscopic MEC contributions and phenomenological 2p2h effects.

Inclusion of relativistic effective mass improves the accuracy of scattering predictions.

Abstract

The quasielastic cross-section of charged-current neutrino and antineutrino scattering on $^{12}$C is calculated using an improved superscaling model with relativistic effective mass. Our model encompasses two-particle emission induced by neutrinos, which we distinguish into two contributions. The first contribution arises from meson-exchange currents, and its calculation is performed at a microscopic level. The second contribution is phenomenological and extracted from the high-energy tail of the scaling function, assumed to be produced by 2p2h mechanisms where the one-body current plays a role, such as short-range correlations and interferences with MEC, final-state interaction, etc. The model explicitly includes the modification of the relativistic effective mass of the nucleon within the relativistic mean field model of nuclear matter. The meson exchange currents are also consistently calculated within the same model. With this model, we present predictions for the neutrino and antineutrino cross sections of $^{12}$C that have been measured in accelerator experiments.