Centre-of-momentum Variables in $\nu_\mu$CC1p1$\pi$

TL;DR

This paper introduces centre-of-momentum variables to better isolate and study final-state interactions in neutrino-nucleus interactions, enabling more accurate FSI modeling and cross-experiment comparisons.

Contribution

It presents a novel set of centre-of-momentum variables, $ heta_{ extrm{COM}}$ and $E_{ extrm{COM}}$, that effectively isolate FSI effects with minimal dependence on initial state and flux.

Findings

Variables can distinguish FSI contributions effectively.

Minimal dependence on nuclear initial state and neutrino flux.

Enables direct cross-comparison of neutrino cross-sections.

Abstract

This study introduces a novel set of variables, namely the centre-of-momentum variables, $\theta_{\textrm{COM}}$ and $E_{\textrm{COM}}$, designed to isolate final-state interactions (FSI) from other aspects of neutrino-nucleus interactions. Through detailed simulation studies, this work demonstrates the ability of these variables to distinguish FSI contributions with minimal dependence on the nuclear initial state and, practically, on the neutrino flux, highlighting their potential for advancing FSI modelling. With high-purity neutrino-hydrogen interaction selections, $\theta_{\textrm{COM}}$ offers the first opportunity for a direct cross-comparison among different neutrino cross-section experiments.