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arXiv · 1312.2805

Effective $\theta$ term by CP-odd electromagnetic background fields

Claudio Bonati·Guido Cossu·Massimo D'Elia·Marco Mariti·Francesco Negro
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Abstract

We discuss our study of QCD in the presence of CP-odd electromagnetic (e.m.) background fields. We investigate the propagation of the CP-odd term from the e.m. sector to the strong sector, inducing an effective $\theta$ term. We discuss the method we have used in our lattice QCD simulations, and the results of our analysis, which are relevant to the determination of the effective pseudoscalar QED-QCD interactions. We also explore how these CP-odd e.m. background fields influence the number of the Dirac zero modes in our configurations.

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Claudio Bonati, Guido Cossu, Massimo D'Elia, Marco Mariti, Francesco Negro. 2013-12-10. Effective $\theta$ term by CP-odd electromagnetic background fields. https://arxiv.org/abs/1312.2805

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