PCAC and coherent pion production by neutrinos

TL;DR

This paper analyzes coherent pion production by neutrinos at low energies using PCAC theory, highlighting lepton mass effects and comparing predictions with experimental data, finding good agreement with some limits but discrepancies with recent results.

Contribution

It applies pion carbon scattering data within the PCAC framework to analyze neutrino-induced coherent pion production, offering a model-independent approach.

Findings

Predictions align with existing upper limits for positive pion production.

Results are significantly below MiniBooNE's neutral pion production measurements.

Lepton mass effects play a crucial role in suppressing certain pion production channels.

Abstract

Coherent pion production in low energy neutrino reactions is discussed in the framework of the partially conserved axial vector current theory (PCAC). The role of lepton mass effects in suppressing production of positively charged pions is discussed. Instead of using models of pion nucleus scattering, the available data on pion carbon scattering are implemented for an analysis of the PCAC prediction. Our results agree well with the published upper limits for positively charged production but are much below the recent MiniBooNE result for neutral pion production.