{"title":"New CP phase and exact oscillation probabilities of Dirac neutrino derived from relativistic equation","authors":"Keiichi Kimura , Akira Takamura","doi":"10.1016/j.aop.2025.170040","DOIUrl":null,"url":null,"abstract":"<div><div>We present a new formulation for deriving neutrino oscillation probabilities relativistically, based not on the Schrödinger equation but on the Dirac equation. In the context of two generations, we calculate the oscillation probabilities precisely in a scenario where only the Dirac mass term is present. Our analysis reveals the emergence of two new features in the oscillation probabilities derived from the Dirac equation. The first feature is that the oscillation probabilities depend on the absolute value of the neutrino mass. While it has generally been assumed that oscillation probabilities depend solely on mass squared differences, we show that they also depend on the absolute mass. The second feature is the emergence of a new CP phase. If interactions exist that can distinguish the flavors of right-handed neutrinos in physics beyond the Standard Model, we could potentially observe this new CP phase even in the two-generation model. We discuss the feasibility of detecting the contributions of these features through neutrino oscillations at atomic scales. In contrast, these effects are negligible in conventional short- and long-baseline experiments, and no contradictions arise with previous findings.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"479 ","pages":"Article 170040"},"PeriodicalIF":3.0000,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Annals of Physics","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0003491625001216","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PHYSICS, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
We present a new formulation for deriving neutrino oscillation probabilities relativistically, based not on the Schrödinger equation but on the Dirac equation. In the context of two generations, we calculate the oscillation probabilities precisely in a scenario where only the Dirac mass term is present. Our analysis reveals the emergence of two new features in the oscillation probabilities derived from the Dirac equation. The first feature is that the oscillation probabilities depend on the absolute value of the neutrino mass. While it has generally been assumed that oscillation probabilities depend solely on mass squared differences, we show that they also depend on the absolute mass. The second feature is the emergence of a new CP phase. If interactions exist that can distinguish the flavors of right-handed neutrinos in physics beyond the Standard Model, we could potentially observe this new CP phase even in the two-generation model. We discuss the feasibility of detecting the contributions of these features through neutrino oscillations at atomic scales. In contrast, these effects are negligible in conventional short- and long-baseline experiments, and no contradictions arise with previous findings.
期刊介绍:
Annals of Physics presents original work in all areas of basic theoretic physics research. Ideas are developed and fully explored, and thorough treatment is given to first principles and ultimate applications. Annals of Physics emphasizes clarity and intelligibility in the articles it publishes, thus making them as accessible as possible. Readers familiar with recent developments in the field are provided with sufficient detail and background to follow the arguments and understand their significance.
The Editors of the journal cover all fields of theoretical physics. Articles published in the journal are typically longer than 20 pages.