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PCAC Relation and Pion Production-Absorption in Nuclei

T. Nogi·T. Sato·H. Ohtsubo
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Abstract

Nuclear PCAC relation is studied in the framework of the effective theory of nuclear interaction, in which the interaction of real pion production-absorption is expressed by many-body operators, and does not include the one-nucleon operator as was assumed in the conventional works, while the effective axial-vector current includes the one-nucleon current in contrast to the former interaction. This problem is investigated under the simple linear $σ$-model. Results are as folows: 1) The theory describes consistently the PCAC relation and the pion production-absorption process. 2) The conventional interpretation of the effective pion source function as the interaction Hamiltonian of pion production-absorption does not hold. 3) The effective pion source function still includes the one-nucleon operator for the pion production-absorption at threshold effectively, which may justify the conventional theory.

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T. Nogi, T. Sato, H. Ohtsubo. 2004-09-17. PCAC Relation and Pion Production-Absorption in Nuclei. https://arxiv.org/abs/nucl-th/0409034

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