Il Nuovo Cimento A (1971-1996)

, Volume 48, Issue 2, pp 320–333 | Cite as

Yet another proposal for determining the induced pseudoscalar coupling constant

  • A. Maksymowicz


It has been known for some time that μ capture from the O+ ground state of16O to the first excited O level of16N could, in principle, provide an accurate measurement of the induced pseudoscalar coupling constant in weak interactions. However, the calculation of the rate of this reaction has been hampered by the lack of an accurate wave function for the16N(0) state. We propose that this difficulty could be circumvented by a measurement of the rate of the β-decay from the16N(0) state back to the16O(0+) ground state. The ratio of the μ-capture to β-decay rates turns out to be almost independent of the details of the nuclear wave function and thus should allow a reasonably accurate determination of the induced pseudoscalar coupling constant to be made.

Ещё одно предложение для определения введенной псевдоскалярной константы связи


В течение некоторого времени было известно, что μ-захват из основного 0+ состояния16O на первый возбужденный 0 уровень16N может, в принципе, обеспечить аккуратное измерение введенной псевдосклярной константы связи в слабых взаимодействиях. Однако, вычисление скорости этой реакции было затру-днено из-за недостаточно точного знания волновой функции для16N(0) состояния. Мы предлагаем, что эту трудность можно обойти если измерять скорость β-распада из состояния16N(0) обратно в основное состояние16O(0+). Отношение скоростей μ-захвата и β-распада оказывается почти не зависит от структуры ядерной волновой функции и, следовательно, возможно произвести довольно аккуратное определение введенной псевдоскалярной константы связи.


È noto da qualche tempo che la cattura di μ dallo stato fondamentale 0+ del16O al primo livello 0 eccitato di16N potrebbe, in linea di principio, fornire una misura accurata della costante di accoppiamento pseduoscalare indotto nelle interazioni deboli. Però il calcolo del rapporto di questa reazione è stato ostacolato dalla mancanza di un'accurata funzione d'onda dello stato16N(0). Si propone di superare questa difficoltà misurando il rapporto del decadimento β dallo stato16N(0) allo stato fondamentale16O(0+). La relazione fra i rapporti della cattura di μ e del decadimento β risulta pressocché indipendente dai dettagli della funzione d'onda nucleare e perciò dovrebbe permettere di fare una determinazione ragionevolmente accurata della costante dell'accoppiamento pseudoscalare indotto.


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Copyright information

© Società Italiana di Fisica 1967

Authors and Affiliations

  • A. Maksymowicz
    • 1
  1. 1.CERNGeneva

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