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arXiv · 2111.08040

Long-range axion forces and hadronic CP violation

Shohei Okawa·Maxim Pospelov·Adam Ritz
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Abstract

Axions and other pseudoscalar fields comprise an interesting class of ultralight dark matter candidates, that may independently play a role in solving the strong $CP$ problem. In the presence of $CP$-violating sources, these pseudoscalar fields can develop a coherent non-derivative coupling to nucleons, $\bar g_{aNN}$, thus mediating `mass-mass' and `mass-spin' forces in matter that can be probed experimentally. We revisit the non-perturbative generation of these $CP$-odd axion forces, and refine estimates of $\bar g_{aNN}$ generated by the EDMs and color EDMs of quarks. We also revisit the Standard Model contribution to $CP$-odd axion couplings generated by the phase of the Cabibbo-Kobayashi-Maskawa quark mixing matrix.

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Shohei Okawa, Maxim Pospelov, Adam Ritz. 2021-11-15. Long-range axion forces and hadronic CP violation. https://doi.org/10.1103/physrevd.105.075003

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