Summary
The neutron spectrum, the neutron asymmetry with respect to muon spin direction, and the neutron polarization are calculated as functions of neutron energy for μ-meson capture in deuterium. The total capture rate and the dependence of the rate on the hyperfine state of the mesic atom are given and compared to approximate expressions. The dependence of the observations on the amount of Fermi or Gamow-Teller coupling and on the presence of an effective pseudoscalar coupling is displayed.
Riassunto
Si calcolano lo spettro dei muoni, l’asimmetria dei neutroni rispetto alla direzione dello spin dei muoni e la polarizzazione dei neutroni, come funzioni dell’energia dei neutroni per la cattura dei mesoni μ in deuterio. Si danno il rateo totale della cattura e la sua dipendenza dallo stato iperfino dell’atomo mesico e si confrontano con le espressioni approssimate. Si mette in evidenza la dipendenza delle osservazioni dalla quantità di accoppiamento Fermi o Gamow-Teller e dalla presenza di un accoppiamento pseudoscalare effettivo.
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References
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The absolute rate is obtained by settinga FF = 2G 2 anda GG - 2/3a GP = 2G 2, whereG is the experimental Fermi coupling constant (11) of β-decay,G = 10−5/M 2. The curves omit the high-energy tail of the neutron spectrum which extends to 50 MeV (=1/2(μ -D)).
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The numerical calculations were performed on the Paris IBM-704 electronic computer, and the assistance of MissF. Rattaud is greatly appreciated.
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Überall, H., Wolfenstein, L. Capture of μ-mesons in deuterium. Nuovo Cim 10, 136–149 (1958). https://doi.org/10.1007/BF02859612
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DOI: https://doi.org/10.1007/BF02859612