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arXiv · 1406.2882

Finite-volume corrections to the CP-odd nucleon matrix elements of the electromagnetic current from the QCD vacuum angle

Tarik Akan·Feng-Kun Guo·Ulf-G. Meißner
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Abstract

Nucleon electric dipole moments originating from strong CP-violation are being calculated by several groups using lattice QCD. We revisit the finite volume corrections to the CP-odd nucleon matrix elements of the electromagnetic current, which can be related to the electric dipole moments in the continuum, in the framework of chiral perturbation theory up to next-to-leading order taking into account the breaking of Lorentz symmetry. A chiral extrapolation of the recent lattice results of both the neutron and proton electric dipole moments is performed, which results in $d_n=(-2.7\pm1.2)\times10^{-16}eθ_0$cm and $d_p=(2.1\pm1.2)\times10^{-16}eθ_0$cm.

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Tarik Akan, Feng-Kun Guo, Ulf-G. Meißner. 2014-07-14. Finite-volume corrections to the CP-odd nucleon matrix elements of the electromagnetic current from the QCD vacuum angle. https://doi.org/10.1016/j.physletb.2014.07.022

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