scholarly journals Connecting Electroweak Symmetry Breaking and Flavor: A Light Dilaton D and a Sequential Heavy Quark Doublet Q

Symmetry ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 312
Author(s):  
Wei-Shu Hou
Keyword(s):  
Symmetry Breaking ◽  
Yukawa Coupling ◽  
Vector Boson ◽  
Hadron Collider ◽  
Goldstone Boson ◽  
Gluon Fusion ◽  
New Physics ◽  
Electroweak Symmetry Breaking ◽  
Electroweak Symmetry ◽  
Mass Generation

The 125 GeV boson is quite consistent with the Higgs boson of the Standard Model (SM), but there is a challenge from Anderson as to whether this particle is in the Lagrangian. As Large Hadron Collider (LHC) Run 2 enters its final year of running, we ought to reflect and make sure we have gotten everything right. The ATLAS and CMS combined Run 1 analysis claimed a measurement of 5.4σ vector boson fusion (VBF) production which is consistent with SM, which seemingly refutes Anderson. However, to verify the source of electroweak symmetry breaking (EWSB), we caution that VBF measurement is too important for us to be imprudent in any way, and gluon–gluon fusion (ggF) with similar tag jets must be simultaneous measured, which should be achievable in LHC Run 2. The point is to truly test the dilaton possibility—the pseudo-Goldstone boson of scale invariance violation. We illustrate EWSB by dynamical mass generation of a sequential quark doublet (Q) via its ultrastrong Yukawa coupling and argue how this might be consistent with a 125 GeV dilaton, D. The ultraheavy 2mQ≳4–5 TeV scale explains the absence of New Physics so far, while the mass generation mechanism shields us from the UV theory for the strong Yukawa coupling. Collider and flavor physics implications are briefly touched upon. Current Run 2 analyses show correlations between the ggF and VBF measurements, but the newly observed tt¯H production at LHC poses a challenge.

Links between flavor and electroweak symmetry breaking

2014 ◽  
Vol 29 (21) ◽  
pp. 1444007
Author(s):  
George Wei-Shu Hou
Keyword(s):  
Symmetry Breaking ◽  
Scale Invariance ◽  
Vector Boson ◽  
New Physics ◽  
Electroweak Symmetry Breaking ◽  
Fermion Mass ◽  
Electroweak Symmetry ◽  
Mass Generation ◽  
Gap Equation ◽  
The Standard Model

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.

scholarly journals VARIOUS MODELS MIMICKING THE SM HIGGS BOSON

2012 ◽  
Vol 27 (28) ◽  
pp. 1230030 ◽  
Author(s):  
JUNG CHANG ◽  
KINGMAN CHEUNG ◽  
PO-YAN TSENG ◽  
TZU-CHIANG YUAN
Keyword(s):  
Higgs Boson ◽  
Large Hadron Collider ◽  
Symmetry Breaking ◽  
Vector Boson ◽  
Hadron Collider ◽  
Gluon Fusion ◽  
Electroweak Symmetry Breaking ◽  
Electroweak Symmetry ◽  
Production Mechanism ◽  
The Standard Model

The new particle around 125 GeV observed at the Large Hadron Collider (LHC) is almost consistent with the standard model (SM) Higgs boson, except that the diphoton decay mode may be excessive. We summarize a number of possibilities. While at the LHC the dominant production mechanism for the Higgs boson of SM and some other extensions is via the gluon fusion process, the alternative vector-boson fusion (VBF) is more sensitive to electroweak symmetry breaking. Using the well-known dijet-tagging technique to single out the VBF mechanism, we investigate potential of VBF to discriminate a number of models suggested to give an enhanced inclusive diphoton production rate.

scholarly journals ELECTROWEAK SYMMETRY BREAKING AND THE HIGGS BOSON: CONFRONTING THEORIES AT COLLIDERS

2013 ◽  
Vol 28 (02) ◽  
pp. 1330004 ◽  
Author(s):  
ALEKSANDR AZATOV ◽  
JAMISON GALLOWAY
Keyword(s):  
Higgs Boson ◽  
Symmetry Breaking ◽  
Model Building ◽  
Hadron Collider ◽  
Experimental Tests ◽  
New Physics ◽  
Electroweak Symmetry Breaking ◽  
Electroweak Symmetry ◽  
Parameter Spaces ◽  
Decay Modes

In this review, we discuss methods of parsing direct information from collider experiments regarding the Higgs boson and describe simple ways in which experimental likelihoods can be consistently reconstructed and interfaced with model predictions in pertinent parameter spaces. We review prevalent scenarios for extending the electroweak symmetry breaking sector and emphasize their predictions for nonstandard Higgs phenomenology that could be observed in large hadron collider (LHC) data if naturalness is realized in particular ways. Specifically we identify how measurements of Higgs couplings can be used to imply the existence of new physics at particular scales within various contexts. The most dominant production and decay modes of the Higgs-like state observed in the early data sets have proven to be consistent with predictions of the Higgs boson of the Standard Model, though interesting directions in subdominant channels still exist and will require our careful attention in further experimental tests. Slightly anomalous rates in certain channels at the early LHC have spurred effort in model building and spectra analyses of particular theories, and we discuss these developments in some detail. Finally, we highlight some parameter spaces of interest in order to give examples of how the data surrounding the new state can most effectively be used to constrain specific models of weak scale physics.

scholarly journals DEVIATIONS FROM LOW-ENERGY THEOREM FOR VLVL SCATTERING DUE TO PSEUDO-GOLDSTONE BOSONS

1998 ◽  
Vol 13 (38) ◽  
pp. 3045-3061
Author(s):  
TOMÁS BAHNÍK ◽  
JIŘÍ HOŘEJSÍ
Keyword(s):  
Symmetry Breaking ◽  
Symmetric Space ◽  
Vector Boson ◽  
Goldstone Boson ◽  
Electroweak Symmetry Breaking ◽  
Low Energy ◽  
Tree Level ◽  
Electroweak Symmetry ◽  
Goldstone Bosons ◽  
Vector Bosons

Possible deviations from a low-energy theorem for the scattering of strongly interacting longitudinally polarized W and Z bosons are discussed within a particular scheme of electroweak symmetry breaking. The scheme (suggested earlier by other authors in a slightly different context) is based on spontaneous breakdown of an SU(4) symmetry to custodial SU(2) subgroup. The physical spectrum of such a model contains a set of relatively light pseudo-Goldstone bosons whose interactions with vector bosons modify the low-energy theorem proven for a "minimal" symmetry-breaking sector The Goldstone-boson manifold SU(4)/SU(2) is not a symmetric space. In this context it is observed that, on the other hand, there is a large class of models of electroweak symmetry breaking, involving groups G and H such that the G/H is a symmetric space and the corresponding rich multiplets of pseudo-Goldstone bosons do not influence the canonical low-energy theorem. For the scheme considered here, the relevant interactions are described in terms of an effective chiral Lagrangian and tree-level contributions of the pseudo-Goldstone boson exchanges to the vector boson scattering are computed explicitly. A comparison with the standard model is made.

scholarly journals SEARCHING FOR NEW PHYSICS AT FUTURE ACCELERATORS

2005 ◽  
Vol 20 (22) ◽  
pp. 5184-5192 ◽  
Author(s):  
RICCARDO BARBIERI
Keyword(s):  
Large Hadron Collider ◽  
Symmetry Breaking ◽  
Linear Collider ◽  
Hadron Collider ◽  
New Physics ◽  
Electroweak Symmetry Breaking ◽  
Electroweak Symmetry ◽  
The Status

I overview the status of the Electroweak Symmetry Breaking problem, paying special attention to the possible signals of new physics at the Large Hadron Collider (and at a Linear Collider).

scholarly journals Electroweak Symmetry Breaking and New Physics at the TeV Scale

10.1142/3073 ◽  
1997 ◽  
Author(s):  
Timothy L Barklow ◽  
Sally Dawson ◽  
Howard E Haber ◽  
James L Siegrist
Keyword(s):  
Symmetry Breaking ◽  
New Physics ◽  
Electroweak Symmetry Breaking ◽  
Electroweak Symmetry

scholarly journals TWO COMPOSITE HIGGS DOUBLETS: IS IT THE LOW ENERGY LIMIT OF A NATURAL STRONG ELECTROWEAK SYMMETRY BREAKING SECTOR?

2010 ◽  
Vol 25 (06) ◽  
pp. 423-429 ◽  
Author(s):  
ALFONSO R. ZERWEKH
Keyword(s):  
Higgs Boson ◽  
Symmetry Breaking ◽  
Top Quark ◽  
Gluon Fusion ◽  
Electroweak Symmetry Breaking ◽  
Electroweak Symmetry ◽  
Associated Production ◽  
Composite Higgs ◽  
Main Production ◽  
Model Scheme

In this paper, we propose an effective model scheme that describes the electroweak symmetry breaking sector by means of composite Higgs-like scalars, following the ideas of Minimal Walking Technicolor (MWT). We argue that, because of the general failure of Extended Technicolor (ETC) to explain the mass of the top quark, it is necessary to introduce two composite Higgs bosons: one of them originated by a MWT–ETC sector and the other produced by a Topcolor sector. We focus on the phenomenological differences between the light composite Higgs present in our model and the fundamental Higgs boson predicted by the Standard Model and their production at the LHC. We show that in this scheme the main production channel of the lighter Higgs boson is the associated production with a gauge boson and WW fusion but not the gluon–gluon fusion channel which is substantially suppressed.

TOPOLOGICAL MASS GENERATION, ELECTROWEAK SYMMETRY BREAKING AND BARYOGENESIS

2009 ◽  
Vol 24 (09) ◽  
pp. 703-711
Author(s):  
B. BASU ◽  
P. BANDYOPADHYAY
Keyword(s):  
Phase Transition ◽  
Symmetry Breaking ◽  
Electroweak Symmetry Breaking ◽  
Chiral Anomaly ◽  
Electroweak Theory ◽  
Electroweak Symmetry ◽  
Mass Generation ◽  
Two Stages ◽  
Topological Mass ◽  
Good Agreement

We have studied here electroweak symmetry breaking and baryogenesis from the viewpoint of topological mass generation through chiral anomaly. It is shown that the SU(2) gauge symmetry of the electroweak theory breaks in two stages. In the final stage we have Z-strings produced at the phase transition. We have also studied the problem of baryogenesis in this formalism and the ratio of the baryon–antibaryon is found to be in good agreement with the observed value.

scholarly journals Bootstrap Dynamical Symmetry Breaking

2013 ◽  
Vol 2013 ◽  
pp. 1-19
Author(s):  
Wei-Shu Hou
Keyword(s):  
Symmetry Breaking ◽  
Yukawa Coupling ◽  
Dynamical Symmetry ◽  
Electroweak Symmetry Breaking ◽  
Electroweak Symmetry ◽  
Light Higgs Boson ◽  
Gap Equation ◽  
Dynamical Symmetry Breaking ◽  
Longitudinal Modes ◽  
Goldstone Bosons

Despite the emergence of a 125 GeV Higgs-like particle at the LHC, we explore the possibility of dynamical electroweak symmetry breaking by strong Yukawa coupling of very heavy new chiral quarksQ. Taking the 125 GeV object to be a dilaton with suppressed couplings, we note that the Goldstone bosonsGexist as longitudinal modesVLof the weak bosons and would couple toQwith Yukawa couplingλQ. WithmQ≳700 GeV from LHC, the strongλQ≳4could lead to deeply boundQQ¯states. We postulate that the leading “collapsed state,” the color-singlet (heavy) isotriplet, pseudoscalarQQ¯mesonπ1, isGitself, and a gap equation without Higgs is constructed. Dynamical symmetry breaking is affected via strongλQ, generatingmQwhile self-consistently justifying treatingGas massless in the loop, hence, “bootstrap,” Solving such a gap equation, we find thatmQshould be several TeV, orλQ≳4π, and would become much heavier if there is a light Higgs boson. For such heavy chiral quarks, we find analogy with theπ−Nsystem, by which we conjecture the possible annihilation phenomena ofQQ¯→nVLwith high multiplicity, the search of which might be aided by Yukawa-boundQQ¯resonances.

THE ONE-PARAMETER MODEL AT LHC

2011 ◽  
Vol 26 (02) ◽  
pp. 87-100
Author(s):  
JAMES MAXIN ◽  
VAN E. MAYES ◽  
D. V. NANOPOULOS
Keyword(s):  
Large Hadron Collider ◽  
Symmetry Breaking ◽  
Hadron Collider ◽  
Susy Breaking ◽  
Electroweak Symmetry Breaking ◽  
Electroweak Symmetry ◽  
Brane Model ◽  
String Compactifications ◽  
The One ◽  
Breaking Scale

No-scale supergravity is a framework where it is possible to naturally explain radiative electroweak symmetry breaking and correlate it with the effective SUSY breaking scale. Many string compactifications have a classical no-scale structure, resulting in a one-parameter model (OPM) for the supersymmetry breaking soft terms, which results in a highly constrained subset of mSUGRA. We investigate the allowed supersymmetry parameter space for a generic one-parameter model taking into account the most recent experimental constraints. We also survey the possible signatures which may be observable at the Large Hadron Collider (LHC). Finally, we compare collider signatures of OPM to those from a model with non-universal soft terms, in particular those of an intersecting D6-brane model.

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