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Parity-Violating Pion-Nucleon Coupling h_{πNN}^{(1)} from π^+ Electroproton Production Near the Threshold

Jiunn-Wei Chen·Xiangdong Ji
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Abstract

We study the possibility of measuring parity-violating pion-nucleon coupling h_{πNN}^{(1)} from π^+ electroproton production in the threshold region. We calculate the electron-helicity asymmetry in terms of h_{πNN}^{(1)} and the Z-boson exchange between the electron and proton in leading-order heavy-baryon chiral perturbation theory. From the result, we demonstrate that the coupling can be determined to an accuracy of about 2 10^{-7} in an experiment with incident electron energy 250 MeV, luminosity 10^{38} sec^{-1} cm^{-2}, and a running time of 10^7 sec.

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Jiunn-Wei Chen, Xiangdong Ji. 2000-11-30. Parity-Violating Pion-Nucleon Coupling h_{πNN}^{(1)} from π^+ Electroproton Production Near the Threshold. https://doi.org/10.1016/s0370-2693(01)00100-9

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