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Related papers: Strong CP Violation and large-$N_c$ spin-flavor sy…

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We analyze the CP-violating electric dipole form factor of the nucleon in the framework of covariant baryon chiral perturbation theory. We give a new upper bound on the vacuum angle, |\theta_0| \lesssim 2.5 \cdot 10^{-10}. The quark mass…

High Energy Physics - Phenomenology · Physics 2010-05-07 K. Ottnad , B. Kubis , U. -G. Meißner , F. -K. Guo

We study the effects of the CP-breaking topological $\theta$-term in the large $N_c$ QCD model by Witten, Sakai and Sugimoto with $N_f$ degenerate light flavors. We first compute the ground state energy density, the topological…

High Energy Physics - Theory · Physics 2017-03-08 Lorenzo Bartolini , Francesco Bigazzi , Stefano Bolognesi , Aldo L. Cotrone , Andrea Manenti

We study $SU(3)$ flavor-breaking corrections to the relation between the octet baryon masses and the nucleon-meson CP-violating interactions induced by the QCD $\bar\theta$ term. We work within the framework of $SU(3)$ chiral perturbation…

Nuclear Theory · Physics 2015-11-18 Jordy de Vries , Emanuele Mereghetti , Andre Walker-Loud

We report on the calculation of the CP-violating form factor $F_3$ and the corresponding electric dipole moment for charmed baryons in the spin-1/2 sector generated by the QCD $\theta$-term. We work in the framework of covariant baryon…

High Energy Physics - Phenomenology · Physics 2021-02-03 Y. Ünal , Ulf-G. Meißner

We calculate the neutron electric dipole form factor induced by the CP violating theta-term of QCD, within a perturbative chiral quark model which includes pion and kaon clouds. On this basis we derive the neutron electric dipole moment and…

High Energy Physics - Phenomenology · Physics 2015-06-25 J. Kuckei , Claudio Dib , Amand Faessler , Th. Gutsche , Sergey Kovalenko , V. E. Lyubovitskij , K. Pumsa-ard

In the supersymmetric models, the dominant sources of the hadronic flavor-diagonal CP violation at low energy are the theta term and the chromoelectric dipole moments of quarks. Using QCD sum rules, we estimate the preferred range and the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Maxim Pospelov

In this contribution, baryon axial-vector couplings are studied in the framework of the combined 1/Nc and chiral expansions. This framework is implemented on the basis of the emergent spin-flavor symmetry in baryons at large Nc and HBChPT,…

Nuclear Theory · Physics 2013-03-12 A. Calle Cordon , J. L. Goity

We provide a consistent and complete calculation of the electric dipole moments of the deuteron, helion, and triton in the framework of chiral effective field theory. The CP-conserving and CP-violating interactions are treated on equal…

High Energy Physics - Phenomenology · Physics 2015-05-19 J. Bsaisou , J. de Vries , C. Hanhart , S. Liebig , Ulf-G. Meißner , D. Minossi , A. Nogga , A. Wirzba

On general grounds based on quantum field theory the decay amplitude for $\Sigma^0 \to \Lambda \gamma$ consists of a parity conserving magnetic and a parity violating electric dipole transition moment. Because of the subsequent…

High Energy Physics - Phenomenology · Physics 2018-12-05 Shankar Sunil Nair , Elisabetta Perotti , Stefan Leupold

We investigate the phenomenological constraints on a model where, besides the standard model Higgs sector, there is an effective new strong interaction acting on the third generation of quarks and characterized by a $\theta$-like term. This…

High Energy Physics - Phenomenology · Physics 2009-11-07 G. C. Branco , D. Delepine , R. Gonzalez Felipe

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

We calculate the charge quadrupole and magnetic octupole moments of baryons using a group theoretical approach based on broken SU(6) spin-flavor symmetry. The latter is an approximate symmetry of the QCD Lagrangian which becomes exact in…

High Energy Physics - Phenomenology · Physics 2019-02-28 Alfons J. Buchmann

The couplings and interactions of baryons containing a heavy quark are related by light quark spin-flavor symmetry in the large $N$ limit. The single pion coupling constant which determines all heavy quark baryon-pion couplings is equal to…

High Energy Physics - Phenomenology · Physics 2008-11-26 E. Jenkins

We identify new room for CP violation in lepton flavor violating observables not bound by the electric dipole moment of leptons. By focusing on new physics in the muon-electron sector, we show that CP violation can make its first appearance…

High Energy Physics - Phenomenology · Physics 2024-08-05 Diego Redigolo , Michele Tammaro , Andrea Tesi

We calculate the electric dipole moment of the nucleon induced by the QCD theta term. We use the gradient flow to define the topological charge and use $N_f = 2+1$ flavors of dynamical quarks corresponding to pion masses of $700$, $570$,…

High Energy Physics - Lattice · Physics 2021-01-27 Jack Dragos , Thomas Luu , Andrea Shindler , Jordy de Vries , Ahmed Yousif

This work implements the combined BChPT and 1/Nc expansions for pion-nucleon elastic scattering. The effective theory is based on the baryon sector dynamical spin-flavor SU(4) symmetry emergent in the large Nc limit, whose breaking is…

High Energy Physics - Phenomenology · Physics 2025-06-12 D. Jayakodige , J. L. Goity

The QCD Lagrangian contains a CP violating gluon density term with a physical coefficient $\bar{\theta}$. The upper bound on the electric dipole moment of neutron implies that the value of $\bar{\theta}$ should be extremely small rather…

High Energy Physics - Phenomenology · Physics 2023-07-11 Pei-Hong Gu

The nucleon matrix elements (NMEs) associated with quark chromo-magnetic dipole moments (cMDMs) play a crucial role in determining the CP-odd pion-nucleon couplings induced by quark chromo-electric dipole moments. In recent years, it has…

High Energy Physics - Phenomenology · Physics 2025-04-03 Shohini Bhattacharya , Kaori Fuyuto , Emanuele Mereghetti , Thomas R. Richardson

We revisit the supersymmetric CP problem and find that it can be naturally resolved if the origin of CP violation is closely related to the origin of flavour structures. In this case, the supersymmetry breaking dynamics do not bring in any…

High Energy Physics - Phenomenology · Physics 2009-10-31 S. Abel , D. Bailin , S. Khalil , O. Lebedev

We study the CP phases of the soft supersymmetry breaking terms in string-inspired models with non-universal trilinear couplings. We show that such non-universality plays an important role on all CP violating processes. In particular these…

High Energy Physics - Phenomenology · Physics 2009-10-31 Shaaban Khalil , Tatsuo Kobayashi , Antonio Masiero
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