Dynamical coupled-channels model for neutrino-induced meson productions in resonance region

Abstract

A dynamical coupled-channels (DCC) model for neutrino-nucleon reactions in the resonance region is developed. Starting from the DCC model that we have previously developed through an analysis of πN, γN → πN, ηN, KΛ, KΣ reaction data for W ≤ 2.1 GeV, we extend the model of the vector current to Q 2 ≤ 3.0 (GeV/c) 2 by analyzing electron-induced reaction data for both proton and neutron targets. We derive axial-current matrix elements that are related to the πN interactions of the DCC model through the Partially Conserved Axial Current (PCAC) relation. Consequently, the interference pattern between resonant and non-resonant amplitudes is uniquely determined. We calculate cross sections for neutrino-induced meson productions, and compare them with available data. Our result for the single-pion production reasonably agrees with the data. We also make a comparison with the double-pion production data. Our model is the first DCC model that can give the double-pion production cross sections in the resonance region. We also make comparison of our result with other existing models to reveal an importance of testing the models in the light of PCAC and electron reaction data. The DCC model developed here will be a useful input for constructing a neutrino-nucleus reaction model and a neutrino event generator for analyses of neutrino experiments.

Light-Quark Baryon Spectroscopy from ANL-Osaka Dynamical Coupled-Channels Analysis

“…Finally, the framework of our DCC approach itself is quite general, and it has been applied not only to the light-quark baryon spectroscopy, but also to the neutrino-induced reactions [25,39] associated with the neutrino-oscillation experiments in the multi-GeV region and the meson spectroscopy [40,41]. We plan to put more efforts into these directions, too.…”

“…It is noted that such isospin currents are also necessary for studying neutrino-induced reactions (see e.g., Refs. [25,30]). Currently we use the "neutron"-target data extracted by other analysis groups from the deuterontarget reactions.…”

Axial form factors of the octet baryons in a covariant quark model

“…Models for neutrino/antineutrino scattering based on baryon-meson coupled-channels can be found in Refs. [17][18][19].…”

Modern Dynamical Coupled-Channels Calculations for Extracting and Understanding the Nucleon Spectrum

“…Finally, the theoretical framework of the ANL-Osaka DCC approach itself is quite general, and it has been applied also to the spectroscopy of S = −1 hyperon resonances via the comprehensive analysis of K − p [31,32] and K − d [33] reactions, the meson spectroscopy via the analysis of three-meson decay processes [34,35], and the neutrino-induced reactions [36,37] associated with the neutrinooscillation experiments in the multi-GeV region. More efforts will be put into these directions, too.…”