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arXiv · 2404.13516

Neutron electric dipole moment from isovector quark chromo-electric dipole moment

Tanmoy Bhattacharya·Vincenzo Cirigliano·Rajan Gupta·Emanuele Mereghetti·Jun-Sik Yoo·Boram Yoon
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Abstract

We present results from our lattice QCD study of the contribution of the isovector quark cEDM (qcEDM) operator to the neutron EDM. The calculation was carried out on four 2+1+1-flavor highly improved staggered quark ensembles (provided to us by the MILC collaboration) using Wilson-clover quarks to construct correlation functions. We use the nonsinglet axial Ward identity including corrections up to O(a) to show how to control the power-divergent mixing of the isovector qcEDM operator with the lower dimensional pseudoscalar operator. Results for the nEDM are presented after conversion to the MS scheme at the leading-log order.

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Tanmoy Bhattacharya, Vincenzo Cirigliano, Rajan Gupta, Emanuele Mereghetti, Jun-Sik Yoo, Boram Yoon. 2024-04-21. Neutron electric dipole moment from isovector quark chromo-electric dipole moment. https://arxiv.org/abs/2404.13516

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