Polarization Experiments in the Godfrey-Cycle

  • Laszlo Grenacs
Part of the Ettore Majorana International Science Series book series (volume 4)


From the “new” experiments performed in the A = 12 mass multiplet, viz. i) beta-decay asymmetry of aligned 12B/12N mirror nuclei and ii) the average and longitudinal polarizations of 12B (g.s.) produced by μ-capture in 12C, we learned about the nature of weak interactions:
  • there are no second class axial-vector currents,

  • the weak magnetism is now verified in μ-capture,

  • -the helicity of the “muonic” neutrino is measured with good precision (≃ 10%) (the result agrees with the standard V-A scheme).


Graphite Attenuation Allo Cond 


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    More recent calculations [M. Kobayashi et al., Nucl. Phys. A312 (1978) 377 and W.-Y. Hwang (preprint 1979)] yield Pav(1-) > 0. This affects the value of WM (μ)only very slightly, the value of (gp+gT)/gA becomes 10 ± 2.7 which is still compatible with the PCAC predictionADSGoogle Scholar
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Copyright information

© Plenum Press, New York 1980

Authors and Affiliations

  • Laszlo Grenacs
    • 1
  1. 1.Institut de Physique CorpusculaireUniversité Catholique de LouvainLouvain-la-NeuveBelgium

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