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Related papers: Clearing up the Strong $CP$ problem

200 papers

Recently, it was shown that modular symmetry may solve the strong CP problem without axions, by producing a vanishing QCD angle while generating a large quark CP violation phase. We extend this framework to finite modular groups,…

High Energy Physics - Phenomenology · Physics 2024-10-25 J. T. Penedo , S. T. Petcov

The electric dipole moments (EDMs) of nucleons are sensitive probes of additional $\cal CP$ violation sources beyond the standard model to account for the baryon number asymmetry of the universe. As a fundamental quantity of the nucleon…

High Energy Physics - Phenomenology · Physics 2018-04-25 Tianbo Liu , Zhiwen Zhao , Haiyan Gao

We calculate the electric dipole moments (EDM) of the neutral Hg(199) atom, deuteron, nucleons and neutral hyperons Lambda, Sigma(0) and Xi(0) in the framework of a generic SUSY model without R-parity conservation (RPV SUSY) on the basis of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Amand Faessler , Thomas Gutsche , Sergey Kovalenko , Valery E. Lyubovitskij

The two-nucleon contributions to the electric dipole moment (EDM) of the deuteron, induced by the QCD $\theta$-term, are calculated in the framework of effective field theory up-to-and-including next-to-next-to-leading order. In particular…

High Energy Physics - Phenomenology · Physics 2013-03-13 J. Bsaisou , C. Hanhart , S. Liebig , U. -G. Meißner , A. Nogga , A. Wirzba

We calculate the electric dipole moments of the neutron and the Lambda within the framework of heavy baryon chiral perturbation theory. They are induced by strong CP-violating terms of the effective Lagrangian in the presence of the vacuum…

High Energy Physics - Phenomenology · Physics 2009-10-31 B. Borasoy

We report on a new measurement of the CP-violating permanent Electric Dipole Moment (EDM) of the neutral $^{129}$Xe atom. Our experimental approach is based on the detection of the free precession of co-located nuclear spin-polarized $^3$He…

It is shown that in the scheme with a rotating fermion mass matrix (i.e. one with a scale-dependent orientation in generation space) suggested earlier for explaining fermion mixing and mass hierarchy, the theta-angle term in the QCD action…

High Energy Physics - Phenomenology · Physics 2011-01-27 J. Bordes , H. M. Chan , S. T. Tsou

We present Lattice QCD results on the neutron tensor charges including, for the first time, a simultaneous extrapolation in the lattice spacing, volume, and light quark masses to the physical point in the continuum limit. We find that the…

High Energy Physics - Lattice · Physics 2016-01-11 Tanmoy Bhattacharya , Vincenzo Cirigliano , Rajan Gupta , Huey-Wen Lin , Boram Yoon

The experimental search for CP violation in paramagnetic atomic and molecular systems has made impressive progress in recent years. This has led to strong upper limits on the electron electric dipole moment. The same measurements can also…

High Energy Physics - Phenomenology · Physics 2025-10-24 Heleen Mulder , Rob Timmermans , Jordy de Vries

In any finite system, the presence of a non-zero permanent electric dipole moment (EDM) would indicate CP violation beyond the small violation predicted in the Standard Model. Here, we use the ab initio no-core shell model (NCSM) framework…

Nuclear Theory · Physics 2021-08-23 Paul Froese , Petr Navratil

Searches for CP violating effects in atoms and molecules provide important constrains on competing extensions to the standard model of elementary particles. In particular, CP violation in an atom leads to the CP-odd (T,P-odd) polarizability…

High Energy Physics - Experiment · Physics 2014-11-17 Boris Ravaine , M. G. Kozlov , Andrei Derevianko

We propose a model of soft CP violation that evades the strong CP problem and can describe observed CP violation in the neutral kaon sector, both direct and indirect. Our model requires two ``duark'' mesons carrying quark number two that…

High Energy Physics - Phenomenology · Physics 2009-11-07 Paul H. Frampton , Sheldon L. Glashow , Tadashi Yoshikawa

We argue that CP violation has rather dramatic impact on the "gravity as the weakest force" conjecture. Namely we find that new ultraviolet scale must be $\Lambda \lesssim \theta g^3 M_P$, where $\theta$ is an effective parameter describing…

High Energy Physics - Theory · Physics 2008-07-05 Archil Kobakhidze

The discrete symmetry D_12 at the electroweak scale is used to fix the quark and lepton mixing angles. At the leading order, the Cabbibo angle theta_C is 15^o, and the PMNS matrix is of a bi-dodeca-mixing form giving the Solar-neutrino…

High Energy Physics - Phenomenology · Physics 2011-03-01 Jihn E. Kim , Min-Seok Seo

We calculate the electric dipole moment for the electron and neutron in the framework of the 3-3-1 model with heavy charged leptons. We assume that the only source of $CP$ violation arises from a complex trilinear coupling constant and the…

High Energy Physics - Phenomenology · Physics 2015-01-13 G. De Conto , V. Pleitez

The constraints of electric dipole moments (EDMs) of electron and neutron on the parameter space in supergravity (SUGRA) models with nonuniversal gaugino masses are analyzed. It is shown that with a light sparticle spectrum, the sufficient…

High Energy Physics - Phenomenology · Physics 2016-09-06 Chao-Shang Huang , Liao Wei

The strong CP problem can be solved if the laws of nature are invariant under a space-time parity exchanging the Standard Model with its mirror copy. We review and extend different realizations of this idea with the aim of discussing Dark…

High Energy Physics - Phenomenology · Physics 2023-10-23 Michele Redi , Andrea Tesi

We introduce the strong CP-violation in the framework of AdS/QCD model and calculate the electric dipole moments of nucleons as well as the CP-violating pion-nucleon coupling. Our holographic estimate of the electric dipole moments gives…

High Energy Physics - Phenomenology · Physics 2008-11-26 Deog Ki Hong , Hyun-Chul Kim , Sanjay Siwach , Ho-Ung Yee

Considerable theoretical efforts have gone into expanding the reach of the QCD axion beyond its canonical mass--decay-constant relation. The $Z_\mathcal{N}$ QCD axion model reduces the QCD axion mass naturally, by invoking a discrete…

High Energy Physics - Phenomenology · Physics 2026-02-24 Raymond T. Co , Taegyu Lee , Owen P. Leonard

We propose a model of soft CP violation that evades the strong CP problem and can describe observed CP violation in the neutral kaon sector, both direct and indirect. Our model requires two ``duark'' mesons carrying quark number two that…

High Energy Physics - Phenomenology · Physics 2017-08-23 Paul H. Frampton