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arXiv · 2302.04647

Recoil contributions in neutron beta decay and their corrections to the correlation coefficients

Hui-Yun Cao·Hai-Qing Zhou
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Abstract

In this work, the recoil corrections to the correlation coefficients in the neutron beta decay with polarized neutron and electron are evaluated to order O(m_n^-2) in the Born approximation. Different from the usual calculations applied in the literatures where the phase space factor and the amplitude are expanded independently, we directly expand the full differential scattering cross section and then integrate the solid angles of the neutrino. Furthermore, the most general coupling forms in Wpn are kept in the calculation and the analytic expressions for the angular correlation coefficients are given. The numerical comparisons between the results by the different treatments of the phase space factor and the different choices of the coupling parameters are also presented. The results show that the careful treatment of the expansion on m_n^-1 and the inclusion of the general coupling forms are necessary when aiming to reach the precision 10^-5

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Hui-Yun Cao, Hai-Qing Zhou. 2023-02-09. Recoil contributions in neutron beta decay and their corrections to the correlation coefficients. https://arxiv.org/abs/2302.04647

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