scholarly journals LOW ENERGY DATA AND A MODEL OF FLAVOR MIXING

1999 ◽  
Vol 14 (22) ◽  
pp. 1487-1496 ◽  
Author(s):  
EHAB MALKAWI ◽  
C.-P. YUAN
Keyword(s):  
B Mesons ◽  
Low Energy ◽  
Boson Mass ◽  
Energy Data ◽  
The Third ◽  
Quark Sector ◽  
Flavor Changing ◽  
Heavy Gauge Boson ◽  
Flavor Mixing ◽  
Gauge Boson Mass

We consider a model in which the third family fermions are subjected to an SU(2) interaction different from the first two family fermions. Constrained by the Z-pole data, the heavy gauge boson mass is bounded from below to be about 1.7 TeV at the 2σ level. In this model, the flavor mixing between τ and μ can be so large that [Formula: see text] and Br (τ→μμμ) provide a better constraint than the LEP/SLC data in some region of parameter space. Furthermore, flavor-changing neutral currents are unavoidable in the quark sector of the model. Significant effects to the [Formula: see text] mixing and the rare decays of the K and B mesons, such as [Formula: see text], [Formula: see text], Bs→τ+τ-, μ+μ- and Bs,d→μ±τ∓, are expected.

CP-ASYMMETRIES IN NEUTRAL B-MESON DECAYS IN A CLASS OF LEFT-RIGHT SYMMETRIC MODELS

1996 ◽  
Vol 11 (04) ◽  
pp. 299-306
Author(s):  
W.K. SZE ◽  
HERNG YAO
Keyword(s):  
Standard Model ◽  
B Mesons ◽  
B Meson ◽  
Standard Model Prediction ◽  
Boson Mass ◽  
Neutral B Meson ◽  
The Standard Model ◽  
Mixing Matrix ◽  
Gauge Boson Mass ◽  
Cp Asymmetries

In left-right symmetric models with a general right-handed quark mixing matrix VR, CP-asymmetries of neutral B-mesons can deviate appreciably from the standard model prediction. By assuming a Gronau-Wakaizumi (GW) form of VR, we calculate asymmetries of B0 decays to two-body CP-eigenstates for various possible right-handed gauge boson mass MR. It is found that these CP-asymmetries show a sharp transition from the GW results to the standard model ones in the neighborhood of MR≃800 GeV .

A revisit of the quark mass spectra and flavor mixing based on the S3 flavor symmetry

2016 ◽  
Vol 31 (24) ◽  
pp. 1650131 ◽  
Author(s):  
Ji Xu ◽  
Xinghua Yang ◽  
Deshan Yang
Keyword(s):  
Three Dimensional ◽  
Fine Tuning ◽  
Flavor Symmetry ◽  
Third Generation ◽  
The Third ◽  
Quark Sector ◽  
Three Dimensional Representation ◽  
Down Quark ◽  
Mass Matrices ◽  
Flavor Mixing

In this paper, we propose a simple model based on the S3 flavor symmetry, in which a perturbation ansatz is suggested that the flavor symmetry is explicitly broken down via S3 [Formula: see text]Z2 [Formula: see text] in the up-quark sector and via S3 [Formula: see text]Z3 [Formula: see text] in the down-quark sector. Our model is successful in obtaining the strong hierarchy of mass matrices of both up-type quarks and down-type quarks, but unsuccessful in obtaining the realistic mixing between the third generation and the first two, as in other models based on S3 flavor symmetry proposed in the literature. Through detailed analysis, we find the reason for the unsuccesses in our model which is related to the reducibility of the three-dimensional representation of the S3 group. We conclude that any perturbations in mass matrices preserving the partial symmetry of S3 cannot help getting realistic mixing between the third generation and first two without fine-tuning.

Realizing Stable High‐Performance and Low‐Energy‐Loss Ternary Photovoltaics through Judicious Selection of the Third Component

Solar RRL ◽  
2021 ◽  
pp. 2100450
Author(s):  
Bing-Huang Jiang ◽  
Yi-Peng Wang ◽  
Yu-Wei Su ◽  
Jia-Fu Chang ◽  
Chu-Chen Chueh ◽  
...  
Keyword(s):  
Energy Loss ◽  
High Performance ◽  
Low Energy ◽  
The Third ◽  
Selection Of

scholarly journals The low-energy effective theory of axions and ALPs

2021 ◽  
Vol 2021 (4) ◽  
Author(s):  
Martin Bauer ◽  
Matthias Neubert ◽  
Sophie Renner ◽  
Marvin Schnubel ◽  
Andrea Thamm
Keyword(s):  
High Energy ◽  
New Physics ◽  
Mass Scale ◽  
Low Energy ◽  
Effective Theory ◽  
Loop Order ◽  
Flavor Changing ◽  
Effective Lagrangian ◽  
Anomalous Dimensions ◽  
Pseudoscalar Mesons

Abstract Axions and axion-like particles (ALPs) are well-motivated low-energy relics of high-energy extensions of the Standard Model, which interact with the known particles through higher-dimensional operators suppressed by the mass scale Λ of the new-physics sector. Starting from the most general dimension-5 interactions, we discuss in detail the evolution of the ALP couplings from the new-physics scale to energies at and below the scale of electroweak symmetry breaking. We derive the relevant anomalous dimensions at two-loop order in gauge couplings and one-loop order in Yukawa interactions, carefully considering the treatment of a redundant operator involving an ALP coupling to the Higgs current. We account for one-loop (and partially two-loop) matching contributions at the weak scale, including in particular flavor-changing effects. The relations between different equivalent forms of the effective Lagrangian are discussed in detail. We also construct the effective chiral Lagrangian for an ALP interacting with photons and light pseudoscalar mesons, pointing out important differences with the corresponding Lagrangian for the QCD axion.

scholarly journals The LHC Higgs boson discovery: Implications for Finite Unified Theories

2014 ◽  
Vol 29 (18) ◽  
pp. 1430032 ◽  
Author(s):  
S. Heinemeyer ◽  
M. Mondragón ◽  
G. Zoupanos
Keyword(s):  
Higgs Boson ◽  
Predictive Power ◽  
Low Energy ◽  
Boson Mass ◽  
Higgs Boson Mass ◽  
Light Higgs Boson ◽  
Quark Masses ◽  
Grand Unified Theories ◽  
Unified Theories ◽  
Discovery Potential

Finite Unified Theories (FUTs) are N = 1 supersymmetric Grand Unified Theories (GUTs) which can be made finite to all-loop orders, based on the principle of reduction of couplings, and therefore are provided with a large predictive power. We confront the predictions of an SU(5) FUT with the top and bottom quark masses and other low-energy experimental constraints, resulting in a relatively heavy SUSY spectrum, naturally consistent with the nonobservation of those particles at the LHC. The light Higgs boson mass is automatically predicted in the range compatible with the Higgs discovery at the LHC. Requiring a light Higgs boson mass in the precise range of Mh= 125.6 ±2.1 GeV favors the lower part of the allowed spectrum, resulting in clear predictions for the discovery potential at current and future pp, as well as future e+e-colliders.

Photoproduction of Gravitational Radiation in Static Electromagnetic Fields. Radiative Corrections

1975 ◽  
Vol 53 (20) ◽  
pp. 2315-2320 ◽  
Author(s):  
G. Papini ◽  
S. -R. Valluri
Keyword(s):  
Cross Section ◽  
Gravitational Radiation ◽  
Low Energy ◽  
Radiative Corrections ◽  
Third Order ◽  
The Third ◽  
Relativistic Approximation ◽  
Effective Lagrangian ◽  
Charge Renormalization ◽  
Made In

The radiative corrections of second and third order for the process of photoproduction of gravitons in Coulomb and magnetic dipole fields have been calculated.All divergences have been removed either by charge renormalization or regularization. No approximations have been made in the calculation of the second order cross section. In the third order calculation only the extreme relativistic approximation is given. The forms of the effective Lagrangian, corresponding to the low energy approximations have been determined.

scholarly journals p-Wave Strength in the Low-energy 7Li(p,?0)8Be Cross Section

1995 ◽  
Vol 48 (5) ◽  
pp. 813 ◽  
Author(s):  
FC Barker
Keyword(s):  
Angular Distribution ◽  
Shell Model ◽  
Cross Section ◽  
Low Energy ◽  
P Wave ◽  
Model Calculations ◽  
Energy Data

Recent fits to low-energy 7Li(p, "Yo)8Be angular distribution and analysing power data suggested a large p-wave strength. It is shown that acceptable fits to the data can be obtained by attributing the p-wave Ml contributions to the tails of the 17 �64 and 18 �15 MeV 1+ levels of 8Be, with p-wave strengths much less than those obtained previously, but only if some of the spectroscopic amplitudes have signs opposite to those suggested by shell model calculations and/or a fit to higher-energy data.

scholarly journals A SCREENING MECHANISM FOR EXTRA W AND Z GAUGE BOSONS

2000 ◽  
Vol 15 (21) ◽  
pp. 3369-3394
Author(s):  
JOAQUIM MATIAS ◽  
ALESSANDRO VICINI
Keyword(s):  
Mass Spectrum ◽  
Gauge Boson ◽  
Extra Dimensions ◽  
Boson Mass ◽  
Gauge Bosons ◽  
Gauge Boson Mass ◽  
Kaluza Klein

We generalize a previous construction of a fermiophobic model to the case of more than one extra W and Z gauge bosons. We focus in particular on the existence of screening configurations and their implication on the gauge boson mass spectrum. One of these configurations allows for the existence of a set of relatively light new gauge bosons, without violation of the quite restrictive bounds coming from the ρ NC parameter. The links with Bess and degenerate Bess models are also discussed. Also the signal given here by this more traditional gauge extension of the SM could help to disentangle it from the towers of Kaluza–Klein states over W and Z gauge bosons in extra dimensions.

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