scholarly journals Higgs boson mass bounds separate models of electroweak symmetry breaking

1996 ◽  
Vol 54 (9) ◽  
pp. 5855-5865 ◽  
Author(s):  
Marco A. Díaz ◽  
Tonnis A. ter Veldhuis ◽  
Thomas J. Weiler
Keyword(s):  
Higgs Boson ◽  
Symmetry Breaking ◽  
Electroweak Symmetry Breaking ◽  
Boson Mass ◽  
Higgs Boson Mass ◽  
Electroweak Symmetry

scholarly journals UNUSUAL HIGGS OR SUPERSYMMETRY FROM NATURAL ELECTROWEAK SYMMETRY BREAKING

2009 ◽  
Vol 24 (21) ◽  
pp. 1631-1648 ◽  
Author(s):  
RADOVAN DERMÍŠEK
Keyword(s):  
Higgs Boson ◽  
Symmetry Breaking ◽  
Electroweak Symmetry Breaking ◽  
Fine Tuning ◽  
Boson Mass ◽  
Higgs Boson Mass ◽  
Electroweak Symmetry ◽  
Supersymmetric Models ◽  
Soft Supersymmetry Breaking ◽  
Search Limit

This review provides an elementary discussion of electroweak symmetry breaking in the minimal and the next-to-minimal supersymmetric models with the focus on the fine-tuning problem — the tension between natural electroweak symmetry breaking and the direct search limit on the Higgs boson mass. Two generic solutions of the fine-tuning problem are discussed in detail: models with unusual Higgs decays; and models with unusual pattern of soft supersymmetry breaking parameters.

scholarly journals STARTLING EQUIVALENCES IN THE HIGGS-GOLDSTONE SECTOR BETWEEN RADIATIVE AND LOWEST-ORDER CONVENTIONAL ELECTROWEAK SYMMETRY BREAKING

2005 ◽  
Vol 20 (27) ◽  
pp. 6241-6246 ◽  
Author(s):  
F. A. CHISHTIE ◽  
V. ELIAS ◽  
T. G. STEELE
Keyword(s):  
Higgs Boson ◽  
Symmetry Breaking ◽  
Electroweak Symmetry Breaking ◽  
Boson Mass ◽  
Higgs Boson Mass ◽  
Electroweak Symmetry ◽  
Decay Widths ◽  
Order Of Magnitude

For the Higgs boson mass of ~ 220 GeV expected to arise from radiative electroweak symmetry breaking, we find the same lowest-order expressions as would be obtained from conventional electroweak symmetry breaking, given the same Higgs boson mass, for Higgs-Goldstone sector scattering processes identified with [Formula: see text], [Formula: see text], as well as for Higgs boson decay widths [Formula: see text], H → ZLZL. The radiatively broken case, however, leads to an order of magnitude enhancement over lowest-order conventional symmetry breaking for scattering processes [Formula: see text], ZLZL → HH, as well as a factor of ~ 30 enhancement for HH → HH.

HIGGS BOSON PRODUCTION VIA Z, W BOSONS AND TOPONIUM IN THE E6 SUPERSTRING MODEL

1988 ◽  
Vol 03 (08) ◽  
pp. 1907-1941 ◽  
Author(s):  
V. BARGER ◽  
K. WHISNANT
Keyword(s):  
Higgs Boson ◽  
Symmetry Breaking ◽  
W Bosons ◽  
Electroweak Symmetry Breaking ◽  
Boson Mass ◽  
Model Parameters ◽  
Boson Production ◽  
Electroweak Symmetry ◽  
Higgs Boson Production ◽  
Analytic Expressions

We examine the production of light Higgs bosons associated with electroweak symmetry-breaking in an E6 superstring model in Z→HZ* decays, in e+e− annihilation and in toponium decays. We find that the couplings of the lightest scalar Higgs boson [Formula: see text] in these models are very similar to those of the standard Higgs boson unless the pseudoscalar P0 in the model has mass ≤Mz. Possible new modes for Higgs boson production not found in the standard model include [Formula: see text] or [Formula: see text] and [Formula: see text] or (H+H−), where [Formula: see text] is the second lightest scalar. We give simple analytic expressions for the Higgs boson masses and mixing angles in the limit that the extra Z′ gauge boson is heavy which clearly shows the production mechanisms that are favored for a given set of model parameters. The lower bound on the mass of the charged Higgs boson associated with the electroweak symmetry breaking is 53 GeV, independent of the Z′ boson mass or mixing; this bound is realized only for very small [Formula: see text] and P0 masses. Toponium decays to [Formula: see text] and H+H− may exist at up to the per cent level for some model parameters. The dominant decay mode for [Formula: see text] could be [Formula: see text], if kinematically allowed, while the principal decays for [Formula: see text] could be [Formula: see text] or [Formula: see text] .

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.

MINIMAL DYNAMICAL SYMMETRY BREAKING OF THE ELECTROWEAK INTERACTIONS AND mtop

1990 ◽  
Vol 05 (32) ◽  
pp. 2675-2682 ◽  
Author(s):  
CHRISTOPHER T. HILL
Keyword(s):  
Higgs Boson ◽  
Symmetry Breaking ◽  
Top Quark ◽  
Dynamical Symmetry ◽  
Boson Mass ◽  
Fourth Generation ◽  
Higgs Boson Mass ◽  
Electroweak Interactions ◽  
200 Gev ◽  
Recent Idea

We review the recent idea of a mechanism for dynamically breaking the symmetries of the electroweak interactions which relies upon the formation of condensates involving the conventional quarks and leptons, such as the top quark. In particular, such a scheme would indicate that the top quark is heavy, greater than or of order 200 GeV, and gives further predictions for the Higgs boson mass. It may be extended to a fourth generation with new strong TeV scale flavor-interactions.

scholarly journals BOSONIC SEESAW AND A SOLUTION TO THE μ PROBLEM IN THE UNPARTICLE PHYSICS

2010 ◽  
Vol 25 (09) ◽  
pp. 691-701
Author(s):  
TATSURU KIKUCHI
Keyword(s):  
Higgs Boson ◽  
Standard Model ◽  
Symmetry Breaking ◽  
Conformal Symmetry ◽  
New Physics ◽  
Electroweak Symmetry Breaking ◽  
Effective Theory ◽  
Electroweak Symmetry ◽  
Hidden Sector ◽  
The Standard Model

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.

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 Is the magnitude of the Peccei–Quinn scale set by the landscape?

2019 ◽  
Vol 79 (11) ◽  
Author(s):  
Howard Baer ◽  
Vernon Barger ◽  
Dibyashree Sengupta ◽  
Hasan Serce ◽  
Kuver Sinha ◽  
...  
Keyword(s):  
Dark Matter ◽  
Susy Breaking ◽  
Electroweak Symmetry Breaking ◽  
Boson Mass ◽  
Global Symmetry ◽  
Higgs Boson Mass ◽  
Electroweak Symmetry ◽  
Misalignment Angle ◽  
Intermediate Scale ◽  
Supersymmetric Models

Abstract The value of the Higgs boson mass plus the lack of signal at LHC13 has led to a naturalness crisis for supersymmetric models. In contrast, rather general considerations of the string theory landscape imply a mild statistical draw towards large soft SUSY breaking terms tempered by the requirement of proper electroweak symmetry breaking where SUSY contributions to the weak scale are not too far from $$m_{weak}\sim 100$$mweak∼100 GeV. Such a picture leads to the prediction that $$m_h\simeq 125$$mh≃125 GeV while most sparticles are beyond current LHC reach. Here we explore the possibility that the magnitude of the Peccei–Quinn (PQ) scale $$f_a$$fa is also set by string landscape considerations within the framework of a compelling SUSY axion model. First, we examine the case where the PQ symmetry arises as an accidental approximate global symmetry from a more fundamental gravity-safe $$\mathbb {Z}_{24}^R$$Z24R symmetry and where the SUSY $$\mu $$μ parameter arises from a Kim-Nilles operator. The pull towards large soft terms then also pulls the PQ scale as large as possible. Unless this is tempered by rather severe (unknown) cosmological or anthropic bounds on the density of dark matter, then we would expect a far greater abundance of dark matter than is observed. This conclusion cannot be negated by adopting a tiny axion misalignment angle $$\theta _i$$θi because WIMPs are also overproduced at large $$f_a$$fa. Hence, we conclude that setting the PQ scale via anthropics is highly unlikely. Instead, requiring soft SUSY breaking terms of order the gravity-mediation scale $$m_{3/2}\sim 10$$m3/2∼10–100 TeV places the mixed axion–neutralino dark matter abundance into the intermediate scale sweet zone where $$f_a\sim 10^{11}$$fa∼1011–$$10^{12}$$1012 GeV. We compare our analysis to the more general case of a generic SUSY DFSZ axion model with uniform selection on $$\theta _i$$θi but leading to the measured dark matter abundance: this approach leads to a preference for $$f_a\sim 10^{12}$$fa∼1012 GeV.

Sign in / Sign up

Export Citation Format

Share Document