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Induced Pseudoscalar Coupling in Muon Capture and Second-Order Corrections

A. L. Barabanov
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Abstract

The hyperfine effect in muon capture rate is analyzed with taking into account of the second-order terms in 1/M in the non-relativistic Hamiltonian. It is shown that in the situation of the dominance of the squared first-order terms the interference of zero-order and second-order terms has no significant influence. General expression for neutrino (recoil nucleus) angular distribution in muon capture by nucleus with non-zero spin is proposed. High sensitivity to $g_P$ of the term related with alignment of the initial mesic atom is discussed in the approximation of dominating Gamow--Teller matrix element.

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A. L. Barabanov. 1999-03-23. Induced Pseudoscalar Coupling in Muon Capture and Second-Order Corrections. https://arxiv.org/abs/nucl-th/9903054

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