scholarly journals Constraining the gauge and scalar sectors of the doublet left-right symmetric model

2020 ◽  
Vol 2020 (9) ◽  
Author(s):  
Véronique Bernard ◽  
Sébastien Descotes-Genon ◽  
Luiz Vale Silva

Abstract We consider a left-right symmetric extension of the Standard Model where the spontaneous breakdown of the left-right symmetry is triggered by doublets. The electroweak ρ parameter is protected from large corrections in this Doublet Left-Right Model (DLRM), contrary to the triplet case. This allows in principle for more diverse patterns of symmetry breaking. We consider several constraints on the gauge and scalar sectors of DLRM: the unitarity of scattering processes involving gauge bosons with longitudinal polarisations, the radiative corrections to the muon ∆r parameter and the electroweak precision observables measured at the Z pole and at low energies. Combining these constraints within the frequentist CKMfitter approach, we see that the fit pushes the scale of left-right symmetry breaking up to a few TeV, while favouring an electroweak symmetry breaking triggered not only by the SU(2)L×SU(2)R bi-doublet, which is the case most commonly considered in the literature, but also by the SU(2)L doublet.

2010 ◽  
Vol 25 (20) ◽  
pp. 3911-3932 ◽  
Author(s):  
HIDENORI S. FUKANO ◽  
FRANCESCO SANNINO

We analyze the constraints on the the vacuum polarization of the Standard Model gauge bosons from a minimal set of flavor observables valid for a general class of models of dynamical electroweak symmetry breaking. We will show that the constraints have a strong impact on the self-coupling and masses of the lightest spin-one resonances. Our analysis is applicable to any four and higher-dimensional extension of the Standard Model reducing to models of dynamical electroweak symmetry breaking.


2017 ◽  
Vol 32 (35) ◽  
pp. 1747008
Author(s):  
K. Tuominen

A fully dynamical origin for the masses of weak gauge bosons and heavy quarks of the Standard Model is considered. Electroweak symmetry breaking and the gauge boson masses arise from new strong dynamics, which leads to the appearance of a composite scalar in the spectrum of excitations. In order to generate mass for the Standard Model fermions, we consider extended gauge dynamics, effectively represented by four fermion interactions at presently accessible energies. By systematically treating these interactions, we show that they lead to a large reduction of the mass of the scalar resonance. Therefore, interpreting the scalar as the recently observed 125 GeV state, implies that the mass originating solely from new strong dynamics can be much heavier, of the order of 1 TeV. The couplings of the scalar resonance with the Standard Model gauge bosons and fermions are evaluated, and found to be compatible with the current LHC results.


2012 ◽  
Vol 86 (9) ◽  
Author(s):  
Chun Du ◽  
Hong-Jian He ◽  
Yu-Ping Kuang ◽  
Bin Zhang ◽  
Neil D. Christensen ◽  
...  

2003 ◽  
Vol 18 (14) ◽  
pp. 967-975 ◽  
Author(s):  
J. G. KÖRNER ◽  
CHUN LIU

A supersymmetric model with two copies of the Standard Model gauge groups is constructed in the gauge mediated supersymmetry breaking scenario. The supersymmetry breaking messengers are in a simple form. The Standard Model is obtained after first step gauge symmetry breaking. In the case of one copy of the gauge interactions being strong, a scenario of electroweak symmetry breaking is discussed, and the gauginos are generally predicted to be heavier than the sfermions.


2014 ◽  
Vol 89 (1) ◽  
Author(s):  
Emidio Gabrielli ◽  
Matti Heikinheimo ◽  
Kristjan Kannike ◽  
Antonio Racioppi ◽  
Martti Raidal ◽  
...  

2014 ◽  
Vol 29 (21) ◽  
pp. 1444007
Author(s):  
George Wei-Shu Hou

Fermion mass generation in the standard model was invented by Weinberg, while it is an old notion that strong Yukawa coupling could be the agent of electroweak symmetry breaking. Observation of the 126 GeV boson has crashed the prospects for such a heavy chiral quark doublet Q. However, the dilaton possibility can only be ruled out by confirming vector boson fusion with Run 2 data at the LHC, which starts only in 2015. We recast the [Formula: see text] condensation scenario as Fermi–Yang model v2.0. A Gap Equation has been constructed, with numerical solution demonstrating dynamical mQ generation; scale invariance of this equation may be consistent with a dilaton. Other consequences to be checked are [Formula: see text] "annihilation stars," and enhanced Bd →μ+μ-, KL →π0νν, and possibly sin ϕs. If verified in Nature, the Agent of BEH mechanism would differ from current perception, the 126 GeV boson would be the first New Physics at the LHC, and we would have enough CP violation for baryogenesis.


1996 ◽  
Vol 11 (03) ◽  
pp. 247-255
Author(s):  
M.V. RAMANA

We calculate the production rate of gauge-boson pairs at e+e− colliders in a model with a “hidden” electroweak symmetry breaking sector, i.e. one in which there is a large number of particles in the symmetry breaking sector other than the W± and Z0. We show that the background exceeds the two gauge-boson fusion signals of electroweak symmetry breaking. This implies that in order to explore this model we must be prepared to observe final states other than gauge-bosons.


2010 ◽  
Vol 25 (09) ◽  
pp. 691-701
Author(s):  
TATSURU KIKUCHI

Recently, conceptually new physics beyond the Standard Model has been proposed by Georgi, where a new physics sector becomes conformal and provides "unparticle" which couples to the Standard Model sector through higher dimensional operators in low energy effective theory. Among several possibilities, we focus on operators involving the unparticle and Higgs boson. Once the Higgs develops the vacuum expectation value (VEV), the conformal symmetry is broken and as a result, the mixing between the unparticle and the Higgs boson emerges. In the former part of this paper, we consider a natural realization of bosonic seesaw in the context of unparticle physics. In this framework, the negative mass squared or the electroweak symmetry breaking vacuum is achieved as a result of mass matrix diagonalization. So, the bosonic seesaw mechanism for the electroweak symmetry breaking can naturally be understood in the framework of unparticle physics. In the latter part of this paper, we consider the unparticle as a hidden sector of supersymmetry breaking, and give some phenomenological consequences of this scenario. The result shows that there is a possibility for the unparticle as a hidden sector in SUSY breaking sector, and can provide a solution to the μ problem in SUSY models.


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