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Title: What is the criterion for a strong first order electroweak phase transition in singlet models?

Abstract

It is widely believed that the existence of singlet scalars in some standard model extensions can easily make the electroweak phase transition strongly first order, which is needed for the electroweak baryogenesis scenario. In this paper, we will examine the strength of the electroweak phase transition in the simplest extension of the standard model with a real singlet using the sphaleron energy at the critical temperature. We find that the phase transition is stronger by adding a singlet; and also that the criterion for a strong phase transition {omega}(T{sub c})/T{sub c} > or approx. 1, where {omega}=({upsilon}{sup 2}+(x-x{sub 0}){sup 2}){sup 1/2} and x (x{sub 0}) is the singlet vev in the broken (symmetric) phase, is not valid for models containing singlets, even though often used in the literature. The usual condition {upsilon}{sub c}/T{sub c} > or approx. 1 is more meaningful, and it is satisfied for a large part of the parameter space for physically allowed Higgs masses.

Authors:
 [1];  [2]
  1. Faculty of Physics, University of Bielefeld, Postfach 100131, D-33501 Bielefeld (Germany)
  2. (Algeria)
Publication Date:
OSTI Identifier:
21020364
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.75.083522; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COSMOLOGY; CRITICAL TEMPERATURE; HIGGS BOSONS; HIGGS MODEL; INTERMEDIATE BOSONS; PHASE TRANSFORMATIONS; REST MASS; SCALARS; SPACE; STANDARD MODEL

Citation Formats

Ahriche, Amine, and Department of Physics, University of Jijel, BP 98, Ouled Aissa, DZ-18000 Jijel. What is the criterion for a strong first order electroweak phase transition in singlet models?. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.083522.
Ahriche, Amine, & Department of Physics, University of Jijel, BP 98, Ouled Aissa, DZ-18000 Jijel. What is the criterion for a strong first order electroweak phase transition in singlet models?. United States. doi:10.1103/PHYSREVD.75.083522.
Ahriche, Amine, and Department of Physics, University of Jijel, BP 98, Ouled Aissa, DZ-18000 Jijel. Sun . "What is the criterion for a strong first order electroweak phase transition in singlet models?". United States. doi:10.1103/PHYSREVD.75.083522.
@article{osti_21020364,
title = {What is the criterion for a strong first order electroweak phase transition in singlet models?},
author = {Ahriche, Amine and Department of Physics, University of Jijel, BP 98, Ouled Aissa, DZ-18000 Jijel},
abstractNote = {It is widely believed that the existence of singlet scalars in some standard model extensions can easily make the electroweak phase transition strongly first order, which is needed for the electroweak baryogenesis scenario. In this paper, we will examine the strength of the electroweak phase transition in the simplest extension of the standard model with a real singlet using the sphaleron energy at the critical temperature. We find that the phase transition is stronger by adding a singlet; and also that the criterion for a strong phase transition {omega}(T{sub c})/T{sub c} > or approx. 1, where {omega}=({upsilon}{sup 2}+(x-x{sub 0}){sup 2}){sup 1/2} and x (x{sub 0}) is the singlet vev in the broken (symmetric) phase, is not valid for models containing singlets, even though often used in the literature. The usual condition {upsilon}{sub c}/T{sub c} > or approx. 1 is more meaningful, and it is satisfied for a large part of the parameter space for physically allowed Higgs masses.},
doi = {10.1103/PHYSREVD.75.083522},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 75,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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