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Angular-momentum components of the rho-meson

Компоненты момента ρ-меэона

  • Published:
Il Nuovo Cimento A (1965-1970)

Summary

A model is investigated in which the rho-meson is described as a « quark-quark » pair in anL=1 orbital-angular-momentum state. This model is in line with suggestions obtained from applications ofSL 3,R algebra. By attributing the large spread in energies of the rho to a spread in orbital rotational energies, we conclude that the rho has a corresponding spread in angular-momentum values: the rho is in a pureL=1 state only at the peak of the resonance. A quantitative comparison of calculations with a recent Berkeley ππ phase-shift analysis appears to substantiate this viewpoint. This model, which reproduces the properties of the rho-meson, is readily extended to reproduce the properties of the ω-meson.

Riassunto

Si studia un modello in cui il mesone ρ è descritto come una coppia « quark-quark » in uno stato di momento angolare orbitaleL=1. Tale modello risulta in linea con suggerimenti ottenuti da applicazioni dell’algebra diSL 3,R . Attribuendo l’ampio sparpagliamento dei valori dell’energia del mesone ρ ad uno sparpagliamento delle energie rotazionali orbitali, si conclude che il mesone ρ possiede un corrispondente sparpagliamento dei valori del momento angolare: il mesone ρ è in un puro stato conL=1 soltanto al picco della risonanza. Un confronto quantitativo dai calcoli con una recente analisi degli spostamenti di fase di ππ eseguita a Berkeley convaliderebbe tale punto di vista. Il presente modello, che riproduce la proprietà del mesone ρ, si può estendere facilmente alla rappresentazione delle proprietà del mesone ω.

Реэюме

Исследуется модель, в которой ρ-меэон описывается, как пара « кварк-кварк » в состоянии с орбитальным моментомL=1. Эта модель находится в соответствии с реэультатами, полученными с применением алгебрыSL 3,R . Приписывая больщой раэброс в знергиях ρ-меэона, раэбросу в орбитальных враша-тельных знергиях, мы эаключаем, что ρ-меэон имеет соответствуюший раэброс в эначениях момента, ρ-меэон находится в чистомL=1 состоянии только в пике реэонанса. Количественное сравнение вычислений с недавним аналиэом ππ фаэовых сдвигов Беркли, ио-видимому, подтверждает зту точку эрения. Эта модель, которая воспроиэводит свойства ρ-меэона, легко обобшается, чтобы воспроиэвести свойства ω-меэона.

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  1. Lawrence Livermore Laboratory, University of California, Livermore, Cal.

    M. H. Mac Gregor

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Mac Gregor, M.H. Angular-momentum components of the rho-meson. Nuov Cim A 18, 169–187 (1973). https://doi.org/10.1007/BF02722824

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