scholarly journals Flavor symmetries in the Yukawa sector of non-supersymmetric SO(10): numerical fits using renormalization group running

2021 ◽  
Vol 2021 (9) ◽  
Author(s):  
Tommy Ohlsson ◽  
Marcus Pernow
Keyword(s):  
Renormalization Group ◽  
Mass Parameter ◽  
Double Beta Decay ◽  
Type I ◽  
Flavor Symmetries ◽  
Fitting Procedure ◽  
Mixing Parameters ◽  
Fermion Masses ◽  
Renormalization Group Equations ◽  
Yukawa Sector

Abstract We consider a class of SO(10) models with flavor symmetries in the Yukawa sector and investigate their viability by performing numerical fits to the fermion masses and mixing parameters. The fitting procedure involves a top-down approach in which we solve the renormalization group equations from the scale of grand unification down to the electroweak scale. This allows the intermediate scale right-handed neutrinos and scalar triplet, involved in the type I and II seesaw mechanisms, to be integrated out at their corresponding mass scales, leading to a correct renormalization group running. The result is that, of the 14 models considered, only two are able to fit the known data well. Both these two models correspond to ℤ2 symmetries. In addition to being able to fit the fermion masses and mixing parameters, they provide predictions for the sum of light neutrino masses and the effective neutrinoless double beta decay mass parameter, which are both within current observational bounds.

scholarly journals Leptogenesis and fermion mass fit in a renormalizable SO(10) model

2021 ◽  
Vol 2021 (12) ◽  
Author(s):  
V. Suryanarayana Mummidi ◽  
Ketan M. Patel
Keyword(s):  
Numerical Solutions ◽  
Double Beta Decay ◽  
Fermion Mass ◽  
Strong Correlations ◽  
Yukawa Couplings ◽  
Mixing Parameters ◽  
Fermion Masses ◽  
The Standard Model ◽  
The Right ◽  
Yukawa Sector

Abstract A non-supersymmetric renormalizable SO(10) model is investigated for its viability in explaining the observed fermion masses and mixing parameters along with the baryon asymmetry produced via thermal leptogenesis. The Yukawa sector of the model consists of complex 10H and $$ {\overline{126}}_H $$ 126 ¯ H scalars with a Peccei-Quinn like symmetry and it leads to strong correlations among the Yukawa couplings of all the standard model fermions including the couplings and masses of the right-handed (RH) neutrinos. The latter implies the necessity to include the second lightest RH neutrino and flavor effects for the precision computation of leptogenesis. We use the most general density matrix equations to calculate the temperature evolution of flavoured leptonic asymmetry. A simplified analytical solution of these equations, applicable to the RH neutrino spectrum predicted in the model, is also obtained which allows one to fit the observed baryon to photon ratio along with the other fermion mass observables in a numerically efficient way. The analytical and numerical solutions are found to be in agreement within a factor of $$ \mathcal{O}(1) $$ O 1 . We find that the successful leptogenesis in this model does not prefer any particular value for leptonic Dirac and Majorana CP phases and the entire range of values of these observables is found to be consistent. The model specifically predicts (a) the lightest neutrino mass $$ {m}_{v_1} $$ m v 1 between 2–8 meV, (b) the effective mass of neutrinoless double beta decay mββ between 4–10 meV, and (c) a particular correlation between the Dirac and one of the Majorana CP phases.

Fermion masses and mixings in a 3-3-1 model withQ4symmetry

2019 ◽  
Vol 34 (25) ◽  
pp. 1950198
Author(s):  
V. V. Vien ◽  
D. P. Khoi
Keyword(s):  
Neutrino Mass ◽  
Mass Parameter ◽  
Majorana Neutrino ◽  
Tree Level ◽  
Type I ◽  
Inverted Hierarchy ◽  
Quark Masses ◽  
Fermion Masses ◽  
Majorana Neutrino Mass ◽  
Good Agreement

We construct a renormalizable [Formula: see text] model with [Formula: see text] symmetry accommodating the observed pattern of fermion masses and mixings with Dirac CP violation phase. The smallness of the active neutrino masses arises from a combination of type I and type II seesaw mechanisms. Both normal and inverted neutrino mass ordering are viable in our model in which the obtained physical observables of the lepton sector are well consistent with the global fit of neutrino oscillation data [P. F. de Salas et al., Phys. Lett. B 782, 633 (2018)] while the CKM matrix is unity at tree level and the quark masses are in good agreement with the experimental data [Particle Data Group (M. Tanabashi et al.), Phys. Rev. D 98, 030001 (2018)]. Furthermore, the model also predicts an effective Majorana neutrino mass parameter of [Formula: see text] eV for normal hierarchy and [Formula: see text] for inverted hierarchy which are consistent with the constraints given in [P. F. de Salas et al., Phys. Lett. B 782, 633 (2018)].

scholarly journals ONE-LOOP RENORMALIZATION GROUP EQUATIONS OF THE GENERAL FRAMEWORK WITH TWO HIGGS DOUBLET

1999 ◽  
Vol 14 (05) ◽  
pp. 769-798 ◽  
Author(s):  
G. CVETIČ ◽  
S. S. HWANG ◽  
C. S. KIM
Keyword(s):  
Renormalization Group ◽  
Yukawa Coupling ◽  
General Framework ◽  
Vacuum Expectation ◽  
Finite Energy ◽  
Type I ◽  
Gauge Groups ◽  
Special Cases ◽  
Renormalization Group Equations ◽  
Coupling Parameters

Using a finite energy cutoff method, we derive one-loop renormalization group equations (RGE's) for Yukawa coupling parameters of quarks and for the vacuum expectation values of the Higgs doublets in the general framework of the Standard Model with two Higgs doublets (2HDM "type III"). In the model, the neutral-Higgs-mediated flavor-changing neutral currents are allowed but are assumed to be reasonably suppressed at low energies. The popular "type II" and "type I" models are just special cases of this framework. We then compare our RGE results with those of other authors who derived them for general (semi)simple gauge groups. We find out that our one-loop results disagree with those of Vaughn and Machacek, and agree with those of Jack and Osborn. We identify the mistakes of the former authors. We subsequently present a numerical example for the RGE flow of Yukawa coupling parameters and masses of quarks. The example shows a remarkable persistence of the suppression of the neutral-Higgs-mediated FCNC's as the energy of probes increases, in contrast to the usual expectations and reservations about this model.

scholarly journals Renormalization Group and 3-3-1 Model with the DiscreteFlavour Symmetries

2012 ◽  
Vol 22 (1) ◽  
pp. 1-6
Author(s):  
Hoang Ngoc Long ◽  
Nguyen Thi Kim Ngan
Keyword(s):  
Renormalization Group ◽  
Standard Model ◽  
Gauge Group ◽  
Coupling Constants ◽  
Grand Unification ◽  
Flavor Symmetries ◽  
Renormalization Group Equations ◽  
The Standard Model

Renormalization group equations of the 3-3-1 models with A4 and S4 flavor symmetries as the only intermediate gauge group between the standard model and the scale of unification of the three coupling constants are presented. We shall assume that there is no necessarily a group of grand unification at the scale of convergence of the couplings.

scholarly journals Leptogenesis, fermion masses and mixings in a SUSY SU(5) GUT with D4 flavor symmetry

2021 ◽  
Vol 2021 (11) ◽  
Author(s):  
M. Miskaoui ◽  
M. A. Loualidi
Keyword(s):  
Numerical Study ◽  
Double Beta Decay ◽  
Neutrino Masses ◽  
Flavor Symmetry ◽  
Type I ◽  
Yukawa Couplings ◽  
Neutrino Sector ◽  
Fermion Masses ◽  
Predicted Values ◽  
Charged Leptons

Abstract We propose a model of fermion masses and mixings based on SU(5) grand unified theory (GUT) and a D4 flavor symmetry. This is a highly predictive 4D SU(5) GUT with a flavor symmetry that does not contain a triplet irreducible representation. The Yukawa matrices of quarks and charged leptons are obtained after integrating out heavy messenger fields from renormalizable superpotentials while neutrino masses are originated from the type I seesaw mechanism. The group theoretical factors from 24- and 45-dimensional Higgs fields lead to ratios between the Yukawa couplings in agreement with data, while the dangerous proton decay operators are highly suppressed. By performing a numerical fit, we find that the model captures accurately the mixing angles, the Yukawa couplings and the CP phase of the quark sector at the GUT scale. The neutrino masses are generated at the leading order with the prediction of trimaximal mixing while an additional effective operator is required to account for the baryon asymmetry of the universe (BAU). The model is remarkably predictive because only the normal neutrino mass ordering and the lower octant of the atmospheric angle are allowed while the CP conserving values of the Dirac neutrino phase δCP are excluded. Moreover, the predicted values of the effective Majorana mass mββ can be tested at future neutrinoless double beta decay experiments. An analytical and a numerical study of the BAU via the leptogenesis mechanism is performed. We focused on the regions of parameter space where leptogenesis from the lightest right-handed neutrino is successfully realized. Strong correlations between the parameters of the neutrino sector and the observed BAU are obtained.

scholarly journals Data driven flavour model

2020 ◽  
Vol 80 (9) ◽  
Author(s):  
F. Arias-Aragón ◽  
C. Bouthelier-Madre ◽  
J. M. Cano ◽  
L. Merlo
Keyword(s):  
Scalar Potential ◽  
Majorana Neutrino ◽  
Double Beta Decay ◽  
Fermion Mass ◽  
Type I ◽  
Minimal Flavour Violation ◽  
Seesaw Mechanism ◽  
Charged Fermion ◽  
Fermion Masses ◽  
Flavour Violation

AbstractA bottom-up approach has been adopted to identify a flavour model that agrees with present experimental measurements. The charged fermion mass hierarchies suggest that only the top Yukawa term should be present at the renormalisable level. Similarly, describing the lightness of the active neutrinos through the type-I Seesaw mechanism, right-handed neutrino mass terms should also be present at the renormalisable level. The flavour symmetry of the Lagrangian including the fermionic kinetic terms and only the top Yukawa is then a combination of U(2) and U(3) factors. Once considering the Majorana neutrino terms, the associated symmetry is O(3). Lighter charged fermion and active neutrino masses and quark and lepton mixings arise considering specific spurion fields à la Minimal Flavour Violation. The associated phenomenology is investigated and the model turns out to have almost the same flavour protection as the Minimal Flavour Violation in both quark and lepton sectors. Promoting the spurions to dynamical fields, the associated scalar potential is also studied and a minimum is identified such that fermion masses and mixings are correctly reproduced. Very precise predictions for the Majorana phases follow from the minimisation of the scalar potential and thus the neutrinoless-double-beta decay may represent a smoking gun for the model.

scholarly journals IMPLICATIONS OF THE RENORMALIZATION GROUP EQUATIONS IN THREE-NEUTRINO MODELS WITH TWO-FOLD DEGENERACY

2001 ◽  
Vol 16 (23) ◽  
pp. 3923-3930 ◽  
Author(s):  
MU-CHUN CHEN ◽  
K. T. MAHANTHAPPA
Keyword(s):  
Renormalization Group ◽  
Matrix Element ◽  
Exact Solutions ◽  
Beta Decay ◽  
Neutrinoless Double Beta Decay ◽  
Double Beta Decay ◽  
Renormalization Group Equations ◽  
The Matrix ◽  
Complete Set

We obtain a complete set of one-loop RGE's for a set of combinations of neutrino parameters for the case of two-fold degenerate hierarchical three-neutrino models. The requirement of consistency of exact solutions to these RGE's with the two-fold degeneracy yields conditions which have previously been obtained perturbatively/numerically. These conditions, in the limit |Ueν3| = 0, are shown to lead to a strong cancellation in the matrix element of neutrinoless double beta decay.

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