Il Nuovo Cimento A (1965-1970)

, Volume 49, Issue 3, pp 467–478 | Cite as

The concept of antiparticles in particle mixing

  • S. H. Patil
  • Y. Tomozawa
  • York-Peng Yao


We start from the definition that the unstable physical particles are eigenstates of the mixing matrices and consider their relation to the physical antiparticles. When there isCP invariance, the physical antiparticles are theCP-conjugate states of the physical particles. In particular, we show that K 1 0 and K 2 0 behave as particles at all times and to all orders of interactions, irrespectively of the exponential decay law. WhenCP is violated, the question whether the physical antiparticles are theCPT-conjugates of the physical particles is raised. In\(K - \bar K^0 \) system, such a requirement leads to normality of the mixing matrix. However, in ΛΣ0 mixing, this requirement cannot be satisfied, so that in general the antiparticle states cannot be obtained from the particle states byCPT conjugation.


Mass Matrix Physical Particle Unstable Particle Unperturbed State Relativistic Quantum Field Theory 
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Понятие античастиц при смешивании частиц


Мы исходим из определения, что нестабильные физические частицы являются собственными состояниями матриц смешивания, и рассматриваем их связь с физическими античастицами. Если сираведливаCP инвартность, то физические античастицы представляютCP-сопряженные состояния физических уастиц. В частности, мы показываем, что K 1 0 и K 2 0 ведут себя как частицы все время и во всех порядках взаимодействий, независимо от зкспоненциального закона распада. КогдаCP нарушается, возникает вопрос являются ли физические античастицыCPT-сопряженными состояниями физических частиц. В системе\(K - \bar K^0 \) такое требование ведет к нормированию матрицы смешивания. Однако, при смешивании Λ-Σ0 требование не удовлетворяется, так что, в обшем случае, античастичные состояния не могут быть получены из частичных состояний с помошьюCPT-сопряжения.


Si parte dalla definizione delle particelle fisiche instabili come autostati delle matrici di mescolanza e si considera la loro relazione con le antiparticelle fisiche. Quando si ha invarianza rispetto aCP, le antiparticelle fisiche. In particolare si dimostra che K 1 0 e K 2 0 si comportano come particelle sempre e in ogni ordine di interazione, senza riguardo alle leggi di decadimento esponenziale. Se laCP è violata, sorge la questione se le antiparticelle fisiche sono coniugate rispetto alCPT delle particelle fisiche. Nel sisema\(K - \bar K^0 \) questa condizione porta alla normalità della matrice di mescolanza. Però nella mescolanza Λ-Σ0 questa condizione non può essere soddisfatta, cosicchè in generale gli stati di antiparticella non possono essere ottenuti dagli stati di particella per coniugazione rispetto alCPT.


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Copyright information

© Società Italiana di Fisica 1967

Authors and Affiliations

  • S. H. Patil
    • 1
  • Y. Tomozawa
    • 1
  • York-Peng Yao
    • 1
  1. 1.The Institute for Advanced StudyPrinceton

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