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arXiv · 1905.04147

Precision analysis of pseudoscalar interactions in neutron beta decays

A. N. Ivanov·R. Höllwieser·N. I. Troitskaya·M. Wellenzohn·Ya. A. Berdnikov
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Abstract

We analyze the contributions of the one-pion-pole (OPP) exchange, caused by strong low-energy interactions, and the pseudoscalar interaction beyond the Standard Model (BSM) to the correlation coefficients of the neutron beta-decays for polarized neutrons, polarized electrons and unpolarized protons. The strength of contributions of pseudoscalar interactions is defined by the effective coupling constant C_ps = C^(OPP)_ps + C^(BSM)_ps. We show that the contribution of the OPP exchange is of order C^(OPP)_ps ~ - 10^(-5). The effective coupling constant C^(BSM)_ps of the pseudoscalar interaction BSM can be in principle complex. Using the results, obtained by Gonzalez-Alonso et al.( Prog. Part. Nucl. Phys. 104, 165 (2019)) we find that the values of the real and imaginary parts of the effective coupling constant C^(BSM)_ps are constrained by - 3.5x10^{-5} < ReC^(BSM)_ps < 0 and ImC^(BSM)_ps < - 2.3x10^(-5), respectively. The obtained results can be used as a theoretical background for experimental searches of contributions of interactions BSM in asymmetries of the neutron beta-decays with a polarized neutron, a polarized electron and an unpolarized proton at the level of accuracy of a few parts of $10^{-5}$ or even better (Abele, Hyperfine Interact.237, 155 (2016)).

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A. N. Ivanov, R. Höllwieser, N. I. Troitskaya, M. Wellenzohn, Ya. A. Berdnikov. 2019-05-10. Precision analysis of pseudoscalar interactions in neutron beta decays. https://doi.org/10.1016/j.nuclphysb.2019.114891

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