Probing chiral symmetry of nucleon by threshold ηπ production
نویسندگان
چکیده
Double meson production of the eta and pion at the threshold region is investigated in order to determine chiral property of the nucleon. The eta can be used as a probe for the negative parity nucleon N ≡ N(1535) produced in the intermediate state. The coupling of the low energy pion in the final state is then used to extract the sign of the Yukawa coupling, gπN∗N∗ , which distinguishes the two realizations of chiral symmetry, either naive or mirror, for the nucleon.
منابع مشابه
Form factors of the isovector scalar current and the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\eta \pi $$\end{document}ηπ scattering phase shifts
A model for S-wave ηπ scattering is proposed which could be realistic in an energy range from threshold up to above 1 GeV, where inelasticity is dominated by the K K̄ channel. The T -matrix, satisfying two-channel unitarity, is given in a form which matches the chiral expansion results at order p4 exactly for the ηπ → ηπ , ηπ → K K̄ amplitudes and approximately for K K̄ → K K̄ . It contains six phe...
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