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Related papers: Level Crossing Along Sphaleron Barriers

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For successful electroweak baryogenesis to take place through the sphaleron process the universe needs to undergo a strong first order cosmological phase transition. While it does not occur in the Standard Model it becomes possible in the…

High Energy Physics - Phenomenology · Physics 2016-01-19 Anish Ghoshal

We present the analysis of the phase transition for the two Higgs electroweak model. We have found that for a wide range of parameters the universe first tunnels to a new intermediate phase. This feature not only is very important by…

High Energy Physics - Phenomenology · Physics 2009-10-28 Vasilios Zarikas

The recent announcement of a discovery of a possible Higgs-like particle -its spin and parity is yet to be determined- at the LHC with a mass of 126 GeV necessitates a fresh look at the nature of the electroweak symmetry breaking, in…

High Energy Physics - Phenomenology · Physics 2013-09-09 Pham Q. Hung

We present a self-consistent ansatz for a new sphaleron in the electroweak standard model. The resulting field equations are solved numerically. This sphaleron sets the height of the energy barrier for the global SU(2) anomaly.

High Energy Physics - Phenomenology · Physics 2009-10-22 F. R. Klinkhamer

Recently a new dynamical symmetry breaking model of electroweak interactions was proposed based on interacting fermions. Two fermions of different SU(2) representations form a symmetry breaking condensate and generate the lepton and quark…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Cynolter , E. Lendvai

We investigate the effect on the sphaleron in the two Higgs doublet electroweak theory of including CP violation in the Higgs potential. To have better control over the relation between the sphaleron energy and the physical quantities in…

High Energy Physics - Phenomenology · Physics 2016-08-25 Jackie Grant , Mark Hindmarsh

Effect of the electroweak non-conservation of the baryon number could be a key ingredient to explain the ratio of dark and baryonic densities. If dark matter is explained by dark atoms, in which stable -2n charged particles are bound with n…

High Energy Physics - Phenomenology · Physics 2024-01-15 V. A. Beylin , M. Yu. Khlopov , D. O. Sopin

The standard model of electroweak interactions is minimally coupled to gravity and the response of the spherically symmetric solutions -the sphaleron and the bisphaleron- to gravity is emphasized. For a given value of the Higgs mass $M_H$,…

High Energy Physics - Theory · Physics 2010-11-19 Y. Brihaye , M. Desoil

We discuss first-order electroweak phase transition in models with extended Higgs sectors for the case with relatively heavy additional scalar bosons. We first show that, by the combination of the sphaleron decoupling condition,…

High Energy Physics - Phenomenology · Physics 2022-08-31 Shinya Kanemura , Masanori Tanaka

We study the possibility of relaxing the cosmological bound on the Higgs mass coming from the requirement of non-erasure of the baryon asymmetry by sphalerons. After reviewing the Standard Model case we obtain this bound in two extensions…

High Energy Physics - Phenomenology · Physics 2009-09-25 J. R. Espinosa

In very high energy scattering events production of multiple Higgs and electroweak gauge bosons becomes possible. Indeed the perturbative cross section for these processes grows with increasing energy, eventually violating perturbative…

High Energy Physics - Phenomenology · Physics 2015-05-27 Joerg Jaeckel , Valentin V. Khoze

The realisation that the electroweak anomaly can induce significant baryon number violation at high temperature and that the standard models of particle physics and cosmology contain all the ingredients needed for baryogenesis has led to…

High Energy Physics - Phenomenology · Physics 2009-09-25 U. A. yajnik

The Standard Model of particle physics has a number of asymmetries suggestive of a more fundamental theory, where the symmetries are restored. If the symmetry breaking scale is the electroweak scale, new Higgs bosons beyond that of the…

High Energy Physics - Experiment · Physics 2019-08-14 Chris Hays

The discovery of Standard-Model like Higgs at 125 GeV may raise more questions than the answers it provides. In particular, the hierarchy problem remains unsolved, and the Standard Model Higgs quartic self-coupling becomes negative below…

High Energy Physics - Phenomenology · Physics 2023-03-08 Ash Arsenault , Kivanc Y. Cingiloglu , Mariana Frank

We study classically scale invariant models in which the Standard Model Higgs mass term is replaced in the Lagrangian by a Higgs portal coupling to a complex scalar field of a dark sector. We focus on models that are weakly coupled with the…

High Energy Physics - Phenomenology · Physics 2015-06-22 Wolfgang Altmannshofer , William A. Bardeen , Martin Bauer , Marcela Carena , Joseph D. Lykken

Cosmological solutions with a homogeneous Yang-Mills field which oscillates and passes between topologically distinct vacua are discussed. These solutions are used to model the collapsing Bartnik-McKinnon gravitational sphaleron and the…

High Energy Physics - Theory · Physics 2009-10-07 G. W. Gibbons , Alan R. Steif

We propose that the diphoton excess at 750 GeV reported by ATLAS and CMS is due to the decay of an ${\it exo-Higgs}$ scalar $\eta$ associated with the breaking of a new $SU(2)_e$ symmetry, dubbed ${\it exo-spin}$. New fermions, ${\it…

High Energy Physics - Phenomenology · Physics 2016-07-15 Hooman Davoudiasl , Pier Paolo Giardino , Cen Zhang

We study a hybrid model in which the Technicolor and fundamental heavy scalars live together. We concern extreme case, where electroweak symmetry breaking (EWSB) comes almost entirely from the strong dynamics of Technicolor, but the masses…

High Energy Physics - Phenomenology · Physics 2013-04-16 Vladimir Sauli

A dynamical symmetry breaking model of electroweak interactions is investigated based on strongly interacting fermions. Vector-like fermions of different representations of the weak SU(2) form a symmetry breaking condensate and generate the…

High Energy Physics - Phenomenology · Physics 2015-03-18 G. Cynolter , E. Lendvai

In this work we investigate the sphaleron solution in a $SU(2)\times U(1)_X$ gauge theory, which also encompasses the Standard Model, with higher scalar representation(s) ($J^{(i)},X^{(i)}$). We show that the field profiles describing the…

High Energy Physics - Phenomenology · Physics 2014-11-20 Amine Ahriche , Talal Ahmed Chowdhury , Salah Nasri