Il Nuovo Cimento A (1965-1970)

, Volume 12, Issue 3, pp 737–755 | Cite as

Nonlinear chiral lagrangians and the ΔI=1/2 rule

  • G. Riela


A nonlinear chiral Lagrangian with symmetry breaking describing vector, pseudovector and pseudoscalar mesons is constructed. The weak currents deduced via field-current identities are used to compute to zeroth order in (m π 2 /m ρ 2 ) the K → 2π decays. The ΔI=1/2 rule is found to hold and an estimate for the mass of the intermediate vector boson is given.

--Нелнейные киральные лагранжианы и правило ΔI=1/2


Конструируется нелинейный киральный лагранжиан с нарущением симметрии, который описывает векторные, псевдовекторные и псевдоскалярные меэоны. Слабые токи, выведенные череэ полевые токовые тождества, испольэуются для вычисления К → 2π распадов в нулевом порядке поm π 2 /m ρ 2 . Получается, что правило ΔI=1/2 выполняется. Приводится оценка для массы промежуточного векторного боэона.


Si costruisce una lagrangiana chirale non lineare con violazione di simmetria che descrive mesoni vettoriali, pseudovettoriali e pseudoscalari. Le correnti deboli introdotte tramite le identità correnti-campi sono usate per calcolare all’ordine zero inm π 2 /m ρ 2 i decadimenti K→2π. Si trova che la regola di selezione ΔI=1/2 è soddisfatta e si dà una stima della massa del bosone vettoriale intermedio.


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Copyright information

© Società Italiana di Fisica 1972

Authors and Affiliations

  • G. Riela
    • 1
  1. 1.Istituto di Fisica dell’UniversitàPalermo

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