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arXiv · 2003.05390

Neutron Electric Dipole Moments with Clover Fermions

Boram Yoon·Tanmoy Bhattacharya·Vincenzo Cirigliano·Rajan Gupta
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Abstract

We present preliminary results for the contributions to the neutron EDM arising from the QCD $\theta$-term, the Weinberg three-gluon and the quark chromo-EDM operators from our ongoing lattice calculations using clover valence quarks on the MILC HISQ lattices. We use the gradient-flow technique to smooth the lattices and renormalize the gluonic operators, and use the Schwinger source method to incorporate the quark chromo-EDM interactions in the quark propagator. For the QCD $\theta$-term and the Weinberg three-gluon operator, we report results in the gradient-flow scheme from 8 ensembles at four lattice spacings and three pion masses, including 2 physical pion mass ensembles. For the quark chromo-EDM, unrenormalized results are presented at two lattice spacings, $a=0.12$ and $0.09$ fm, and two pion masses, $M_\pi = 310$ MeV and $220$ MeV.

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Boram Yoon, Tanmoy Bhattacharya, Vincenzo Cirigliano, Rajan Gupta. 2020-03-11. Neutron Electric Dipole Moments with Clover Fermions. https://arxiv.org/abs/2003.05390

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