Spontaneous CP violation and horizontal symmetry in the MSSM: toward lepton flavor naturalness

We study the contributions of supersymmetric models with a U(1) horizontal symmetry and only spontaneous CP breaking to various lepton flavor observables, such as μ → eγ and the electron electric dipole moment. We show that both a horizontal symmetry and a lack of explicit CP violation can alleviate the existing bounds from such observables. The undetermined $$ \mathcal{O} $$ O (1) coefficients in such mass matrix models muddle the interpretation of the bounds from various flavor observables. To overcome this, we define a new fine-tuning measure for different observables in such setups. This allows us to study how naturally the observed IR flavor observables can emerge from a given mass matrix model. We use our flavor-naturalness measure in study of our supersymmetric models and quantify the degree of fine tuning required by the bounds from various lepton flavor observables at each mass scale of sleptons, neutralinos, and charginos.

Radiative lepton mass and muon g − 2 with suppressed lepton flavor and CP violations

The recent experimental status, including the confirmation of the muon g − 2 anomaly at Fermilab, indicates a Beyond Standard Model (BSM) satisfying the following properties: 1) it enhances the g − 2 2) suppresses flavor violations, such as μ → eγ, 3) suppresses CP violations, such as the electron electric dipole moment (EDM). In this letter, I show that the eigenbasis of the mass matrix and higher dimensional photon operators can be automatically aligned if the masses of heavy leptons are generated radiatively together with the g − 2. As a result, the muon g − 2 is enhanced but the EDM of the electron and μ → eγ rate are naturally suppressed. Phenomenology and applications of the mechanism to the B-physics anomalies are argued.

Study of HgOH to Assess Its Suitability for Electron Electric Dipole Moment Searches

In search of suitable molecular candidates for probing the electric dipole moment (EDM) of the electron (de), a property that arises due to parity and time-reversal violating (P,T-odd) interactions, we consider the triatomic mercury hydroxide (HgOH) molecule. The impetus for this proposal is based on previous works on two systems: the recently proposed ytterbium hydroxide (YbOH) experiment that demonstrates the advantages of polyatomics for such EDM searches, and the finding that mercury halides provide the highest enhancement due to de compared to other diatomic molecules. We identify the ground state of HgOH as being in a bent geometry, and show that its intrinsic EDM sensitivity is comparable to the corresponding value for YbOH. Along with the theoretical results, we discuss plausible experimental schemes for an EDM measurement in HgOH. Furthermore, we provide pilot calculations of the EDM sensitivity for de for HgCH3 and HgCF3, that are natural extensions of HgOH.

Расчет -=SUP=-179-=/SUP=-HfF-=SUP=-+-=/SUP=- для поиска эффектов нарушения пространственной четности и временной инвариантности

For the 3Δ1 electronic state of the 179Hf 19F+ ion the energy shifts of the hyperfine structure sublevels of the ground rotational state due to the interaction of the electron electric dipole moment (eEDM) and magnetic quadrupole moment (MQM) of the 179Hf nucleus with internal electromagnetic field of the cation were calculated. A feature of eEDM and MKM search experiments on 179Hf 19F+ is the use of rotating external fields, which complicates the calculations and makes them more relevant. Experiments need to know energy levels structure in order to populate them, and knowledge of the g-factors of the levels will allow suppressing a number of systematic errors, related with incomplete control of the magnitude of the used magnetic field. Therefore, the corresponding calculations are also were held. Our calculations can be used to plan an experiment with a cation 179HfF+and interpretation of the obtained data.

Limits on CP-violating hadronic interactions and proton EDM from paramagnetic molecules

Experiments with paramagnetic ground or metastable excited states of molecules (ThO, HfF+, YbF, YbOH, BaF, PbO, etc.) provide strong constraints on the electron electric dipole moment (EDM) and the coupling constant CSP of contact semileptonic interaction. We compute new contributions to CSP arising from the nucleon EDMs due to the combined electric and magnetic electron-nucleon interaction. This allows us to improve limits from the experiments with paramagnetic molecules on the CP-violating parameters, such as the proton EDM, |dp| < 1.1 × 10−23e·cm, the QCD vacuum angle, $$ \left|\overline{\theta}\right| $$ θ ¯ < 1.4 × 10−8, as well as the quark chromo-EDMs and the π-meson-nucleon couplings. Our results may also be used to search for the axion dark matter which produces oscillating $$ \overline{\theta} $$ θ ¯ .

P , T -Violating and Magnetic Hyperfine Interactions in Atomic Thallium

We present state-of-the-art string-based relativistic general-excitation-rank configuration interaction and coupled cluster calculations of the electron electric dipole moment, the nucleon–electron scalar-pseudoscalar, and the magnetic hyperfine interaction constants ( α d e , α C S , A | | , respectively) for the thallium atomic ground state 2 P 1 / 2 . Our present best values are α d e = − 558 ± 28 , α C S = 6.77 ± 0.34 [ 10 − 18 e cm], and A | | = 21172 ± 1059 [MHz]. The central value of the latter constant agrees with the experimental result to within 0.7% and serves as a measurable probe of the P , T -violating interaction constants. Our findings lead to a significant reduction of the theoretical uncertainties for P , T -odd interaction constants for atomic thallium but not to stronger constraints on the electron electric dipole moment, d e , or the nucleon–electron scalar-pseudoscalar coupling constant, C S .