Study of coherence and mixedness in meson and neutrino systems

TL;DR

This paper investigates how coherence and mixedness evolve in meson and neutrino systems, revealing how decoherence effects depend on energy, CP violation, and particle lifetime, using open quantum system models.

Contribution

It introduces a unified analysis of coherence and mixedness in meson and neutrino systems, incorporating decay and decoherence effects with novel insights into CP violation influence.

Findings

Decoherence is negligible in mesons with zero CP violation.

Mixedness increases over particle lifetime.

Maximum decoherence occurs at 30 MeV neutrino energy.

Abstract

We study the interplay between coherence and mixedness in meson and neutrino systems. The dynamics of the meson system is treated using the open quantum system approach taking into account the decaying nature of the system. Neutrino dynamics is studied in the context of three flavor oscillations within the framework of a decoherence model recently used in the context of LSND (Liquid Scintillator Neutrino Detector) experiment. For meson systems, the decoherence effect is negligible in the limit of zero CP violation. Interestingly, the average mixedness increases with time for about one lifetime of these particles. For neutrino system, in the context of the model considered, the decoherence effect is maximum for neutrino energy around 30 MeV. Further, the effect of CP violating phase is found to decrease (increase) the coherence in the upper $0< \delta < \pi$ (lower $\pi < \delta < 2\pi$) half plane.