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

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

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Il Nuovo Cimento A (1965-1970)

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 ratiosξ 0,y 0± ,x 0± with respective isospin transformation propertiesI,I 3=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 definiteSU 3 transformation properties.

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 formaξ 0,y 0± ,x 0± con le rispettive proprietà di trasformazione di isospinI,I 3=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 secondoSU 3.

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,I 3 =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 свойстваSU 3 преобраэований.

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  1. Rutherford High Energy Laboratory, Chilton nr. Didcot, Berks

    J. H. Field

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Field, J.H. General tests of theΔI=1/2 andΔS=ΔQ rules in Kl3 decays. Nuov Cim A 1, 89–96 (1971). https://doi.org/10.1007/BF02722613

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