CP violating interactions are required to realize the matter abundance of our Universe [1]. It is however known that the standard model of particle physics does not contain sufficient CP violation. The electric dipole moment (EDM) is a very sensitive experimental probe of CP violation beyond the standard model, and it is very actively studied in experiments [2].
The EDMs of neutrons, nuclei and atoms have a significant sensitivity to hadronic CP violation, but their quantification has for long been obstructed by the nonperturbative physics of quantum chromodynamics.
Quite recently, the contribution of the Weinberg operator (CP violating three-gluon interaction) [3,4] to the hadron level CP violation has been analyzed [5,6,7], and we are almost attaining the quantification era of the CP violating hadronic interaction in the leading order of standard model effective field theory.
In this talk, we summarize the current attempt to quantify the hadronic CP violation contribution to the EDM of neutrons, nuclei and atoms.
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[2] N. Yamanaka, B.K. Sahoo, N. Yoshinaga, T. Sato, K. Asahi and B.P. Das, Eur. Phys. J. A 53 (2017) 54.
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[4] N. Yamanaka, Int. J. Mod. Phys. E 26, 1730002 (2017).
[5] N. Yamanaka and E. Hiyama, Phys. Rev. D 103, 035023 (2021).
[6] N. Osamura, P. Gubler and N. Yamanaka, JHEP 06 (2022) 072.
[7] N. Yamanaka and M. Oka, Phys. Rev. D 106, 075021 (2022).