Pion-Muon Asymmetry Revisited

TL;DR

This paper revisits an unexplained muon distribution asymmetry from pion decay, proposing an experiment to verify if the effect is physical and to challenge the conventional pseudoscalar pion model.

Contribution

It introduces a new experimental approach to test the muon asymmetry and suggests the pion may be a helicity-zero vector particle, contrary to standard theory.

Findings

Proposes an experiment to confirm the asymmetry as a physical effect.

If confirmed, the pion may be a vector particle, not pseudoscalar.

Challenges existing understanding of pion properties.

Abstract

Long ago an unexpected and unexplainable phenomena was observed. The distribution of muons from positive pion decay at rest was anisotropic with an excess in the backward direction relative to the direction of the proton beam from which the pions were created. Although this effect was observed by several different groups with pions produced by different means, the result was not accepted by the physics community, because it is in direct conflict with a large set of other experiments indicating that the pion is a pseudoscalar particle. It is possible to satisfy both sets of experiments if helicity-zero vector particles exist and the pion is such a particle. Helicity-zero vector particles have direction but no net spin. For the neutral pion to be a vector particle requires an additional modification to conventional theory as discussed herein. An experiment is proposed which can prove that the asymmetry in the distribution of muons from pion decay is a genuine physical effect because the asymmetry can be modified in a controllable manner. A positive result will also prove that the pion is NOT a pseudoscalar particle.