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Il Nuovo Cimento A (1965-1970)

, Volume 1, Issue 1, pp 89–96 | Cite as

General tests of theΔI=1/2 andΔS=ΔQ rules in Kl3 decays

  • J. H. Field
Article

Summary

A complete phenomenological description of Kl3 decays (relative decay rates, angular distributions, momentum spectra and polarizations) can be given in terms of 5 « reduced » form factor ratiosξ0,y ± 0 ,x ± 0 with respective isospin transformation propertiesI,I3=1/2, 1/2; 3/2, 1/2; 3/2, 3/2. Shortcomings of the well-known tests of the ΔI=1/2 rule for Kl3 decays are discussed, and a general test of the formy ± 0 =x ± 0 =0 is proposed. A method is described of extracting the reduced form factor ratios from experimental data. A relation betweeny ± 0 andx ± 0 is given for the case in which theI=3/2 currents have definiteSU3 transformation properties.

Обшая проверка правил ΔI = 1/2 и ΔS = ΔQ в К?3 распадах

Реэюме

Полное феноменологическое описание Кt3 распадов (относительные интенсивности распадов, угловые распределения, импульсные спектры и поляриэации) может быть дано в терминах 5 отнощений «приведенных» форм-факторов ξ0,y ± 0 ,x ± 0 с соответствуюшими свойствами иэоспиновых преобраэованийI,I3 =1/2, 1/2; 3/2, 1/2; 3/2, 3/2. Обсуждаются недостатки хорощо иэвестных проверок правила ΔI = 1/2 Для Кt3 распадов и предлагается обшая проверка формыу ± 0 =x ± 0 =0. Описывается метод иэвлечения отнощений приведенных форм-факторов иэ зкспериментальных данных. Приводится соотнощение междуу ± 0 иу ± 0 для случая, в котором токиI = 3/2 имеют определенные свойстваSU3 преобраэований.

Riassunto

Si può dare una descrizione fenomenologica completa del decadimento Kl3 (rapporti di decadimento relativi, spettri degli impulsi e polarizzazioni) in termini di 5 rapporti « ridotti » dei fattori di formaξ0,y ± 0 ,x ± 0 con le rispettive proprietà di trasformazione di isospinI,I3=1/2, 1/2; 3/2, 1/2; 3/2, 3/2: Si discutono alcuni aspetti non soddisfacenti delle ben note verifiche della regola ΔI=1/2 per il decadimento Kl3, e si propone una verifica generale della formay ± 0 =x ± 0 =0. Si descrive un metodo per estrarre i rapporti ridotti dei fattori di forma dai dati sperimentali. Si dà una relazione fray ± 0 ex ± 0 per il caso in cui le correntiI=3/2 hanno ben definite proprietà di trasformazione secondoSU3.

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References

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Copyright information

© Società Italiana di Fisica 1971

Authors and Affiliations

  • J. H. Field
    • 1
  1. 1.Rutherford High Energy LaboratoryChilton nr. Didcot

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