scholarly journals Estimating the sensitivity of the CERN LHC to electroweak symmetry breaking: Longitudinal-Goldstone boson equivalence as a criterion

1997 ◽  
Vol 55 (5) ◽  
pp. 3038-3067 ◽  
Author(s):  
Hong-Jian He ◽  
Yu-Ping Kuang ◽  
C.-P. Yuan
1992 ◽  
Vol 07 (26) ◽  
pp. 6473-6492 ◽  
Author(s):  
YU. F. PIROGOV

The minimum nonlinear extension SU(3)×U(1)/SU(2)×U(1) to the Standard Model, where the Higgs doublet is a composite Goldstone boson, is investigated. The canonical nonlinear realization of the extended symmetry is constructed in the form maximally close to that of the Standard Model. The corresponding most general effective Lagrangian is built. A simplest linear realization of the extended symmetry in an extended fermion sector is found. The Higgs-Goldstone scenario of the electroweak symmetry breaking is outlined from the standpoint of the multi-TeV energy collider phenomenology.


Symmetry ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 312
Author(s):  
Wei-Shu Hou

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.


1998 ◽  
Vol 13 (38) ◽  
pp. 3045-3061
Author(s):  
TOMÁS BAHNÍK ◽  
JIŘÍ HOŘEJSÍ

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.


2021 ◽  
Vol 2021 (6) ◽  
Author(s):  
Christian W. Bauer ◽  
Nicholas L. Rodd ◽  
Bryan R. Webber

Abstract We compute the decay spectrum for dark matter (DM) with masses above the scale of electroweak symmetry breaking, all the way to the Planck scale. For an arbitrary hard process involving a decay to the unbroken standard model, we determine the prompt distribution of stable states including photons, neutrinos, positrons, and antiprotons. These spectra are a crucial ingredient in the search for DM via indirect detection at the highest energies as being probed in current and upcoming experiments including IceCube, HAWC, CTA, and LHAASO. Our approach improves considerably on existing methods, for instance, we include all relevant electroweak interactions.


2001 ◽  
Vol 16 (13) ◽  
pp. 835-844
Author(s):  
ILIA GOGOLADZE ◽  
MIRIAN TSULAIA

We suggest a new mechanism for electroweak symmetry breaking in the supersymmetric Standard Model. Our suggestion is based on the presence of an anomalous U (1)A gauge symmetry, which naturally arises in the four-dimensional superstring theory, and heavily relies on the value of the corresponding Fayet–Illiopoulos ξ-term.


2016 ◽  
Vol 31 (11) ◽  
pp. 1650065
Author(s):  
Pham Quang Hung ◽  
Nguyen Nhu Le

We present the Higgs mechanism in the context of the EW-scale [Formula: see text] model in which electroweak symmetry is dynamically broken by condensates of mirror quark and right-handed neutrino through the exchange of one fundamental Higgs doublet and one fundamental Higgs triplet, respectively. The formation of these condensates is dynamically investigated by using the Schwinger–Dyson approach. The occurrence of these condensates will give rise to the rich Higgs spectrum. In addition, the VEVs of Higgs fields is also discussed in this dynamical phenomenon.


2022 ◽  
Vol 2022 (01) ◽  
pp. 022
Author(s):  
Nina K. Stein ◽  
William H. Kinney

Abstract We calculate high-precision constraints on Natural Inflation relative to current observational constraints from Planck 2018 + BICEP/Keck(BK15) Polarization + BAO on r and n S, including post-inflationary history of the universe. We find that, for conventional post-inflationary dynamics, Natural Inflation with a cosine potential is disfavored at greater than 95% confidence out by current data. If we assume protracted reheating characterized by w̅>1/3, Natural Inflation can be brought into agreement with current observational constraints. However, bringing unmodified Natural Inflation into the 68% confidence region requires values of T re below the scale of electroweak symmetry breaking. The addition of a SHOES prior on the Hubble Constant H 0 only worsens the fit.


10.1142/3073 ◽  
1997 ◽  
Author(s):  
Timothy L Barklow ◽  
Sally Dawson ◽  
Howard E Haber ◽  
James L Siegrist

Sign in / Sign up

Export Citation Format

Share Document