skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Electric dipole moment constraints on minimal electroweak baryogenesis

Abstract

We study the simplest generic extension of the standard model which allows for conventional electroweak baryogenesis, through the addition of dimension-six operators in the Higgs sector. At least one such operator is required to be CP-odd, and we study the constraints on such a minimal setup, and related scenarios with minimal flavor violation, from the null results of searches for electric dipole moments (EDMs), utilizing the full set of two-loop contributions to the EDMs. The results indicate that the current bounds are stringent, particularly that of the recently updated neutron EDM, but fall short of ruling out these scenarios. The next generation of EDM experiments should be sufficiently sensitive to provide a conclusive test.

Authors:
 [1];  [2];  [3];  [2]
  1. Theoretical Division, Department of Physics, CERN, Geneva 23, CH-1211 (Switzerland)
  2. Department of Physics and Astronomy, University of Victoria, Victoria, BC, V8P 5C2 (Canada)
  3. (Canada)
Publication Date:
OSTI Identifier:
21011020
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevD.75.036006; (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; ELECTRIC DIPOLE MOMENTS; ELECTROMAGNETIC INTERACTIONS; FIELD OPERATORS; HIGGS BOSONS; HIGGS MODEL; MANY-DIMENSIONAL CALCULATIONS; NEUTRONS; STANDARD MODEL; WEAK INTERACTIONS

Citation Formats

Huber, Stephan J., Pospelov, Maxim, Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2J 2W9, and Ritz, Adam. Electric dipole moment constraints on minimal electroweak baryogenesis. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.036006.
Huber, Stephan J., Pospelov, Maxim, Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2J 2W9, & Ritz, Adam. Electric dipole moment constraints on minimal electroweak baryogenesis. United States. doi:10.1103/PHYSREVD.75.036006.
Huber, Stephan J., Pospelov, Maxim, Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2J 2W9, and Ritz, Adam. Thu . "Electric dipole moment constraints on minimal electroweak baryogenesis". United States. doi:10.1103/PHYSREVD.75.036006.
@article{osti_21011020,
title = {Electric dipole moment constraints on minimal electroweak baryogenesis},
author = {Huber, Stephan J. and Pospelov, Maxim and Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2J 2W9 and Ritz, Adam},
abstractNote = {We study the simplest generic extension of the standard model which allows for conventional electroweak baryogenesis, through the addition of dimension-six operators in the Higgs sector. At least one such operator is required to be CP-odd, and we study the constraints on such a minimal setup, and related scenarios with minimal flavor violation, from the null results of searches for electric dipole moments (EDMs), utilizing the full set of two-loop contributions to the EDMs. The results indicate that the current bounds are stringent, particularly that of the recently updated neutron EDM, but fall short of ruling out these scenarios. The next generation of EDM experiments should be sufficiently sensitive to provide a conclusive test.},
doi = {10.1103/PHYSREVD.75.036006},
journal = {Physical Review. D, Particles Fields},
number = 3,
volume = 75,
place = {United States},
year = {Thu Feb 01 00:00:00 EST 2007},
month = {Thu Feb 01 00:00:00 EST 2007}
}
  • A natural solution to the hierarchy problem of the standard model is to assume new physics to appear at the TeV scale. We parametrize the effects of this new physics in terms of an effective Lagrangian and examine its impact on electroweak baryogenesis. We point out that with such an effective Langrangian successful electroweak baryogenesis implies (i) the Higgs boson lies within the reach of CERN LEP II; and (ii) electric dipole moments of the electron and neutron are detectable in the near future.
  • We analyze two-loop gluino corrections to the neutron electric dipole moment (EDM) in the minimal supersymmetry extension of the standard model (MSSM). The dependence of two-loop corrections on the relevant CP violating phases differs from that of the one-loop contributions, and there is a region in the parameter space where the two-loop contributions are comparable with the one-loop contributions. Our numerical results show that the two-loop corrections can be as large as 30% of the one-loop results.
  • The electric dipole moment (EDM) of the top quark is calculated in a model with a vector like multiplet which mixes with the third generation in an extension of the minimal supersymmetric standard model. Such mixings allow for new CP violating phases. Including these new CP phases, the EDM of the top in this class of models is computed. The top EDM arises from loops involving the exchange of the W, the Z as well as from the exchange involving the charginos, the neutralinos, the gluino, and the vector like multiplet and their superpartners. The analysis of the EDM ofmore » the top is more complicated than for the light quarks because the mass of the external fermion, in this case the top quark mass cannot be ignored relative to the masses inside the loops. A numerical analysis is presented and it is shown that the top EDM could be close to 10{sup -19} ecm consistent with the current limits on the EDM of the electron, the neutron and on atomic EDMs. A top EDM of size 10{sup -19} ecm could be accessible in collider experiments such as the International Linear Collider.« less
  • The effective Lagrangian which exhibits explicitly the transmission of the {ital CP}-violating phases induced via the electroweak gaugino masses below the scale of the spontaneous breaking of SU(2){sub {ital L}}{times}U{sub {ital y}}(1) electroweak gauge symmetry is deduced. The formalism is used to compute the one-loop electric dipole moment of the electron including the full set of neutralino states. Contributions of neutralinos other than the photino are found to be significant. It is shown that the current data excludes maximal {ital CP} violation in the electroweak sector except for selectron masses {approx gt}200 GeV and photino masses {approx gt}750 GeV.
  • We address electroweak baryogenesis in the context of composite Higgs models, pointing out that modifications to the Higgs and top quark sectors can play an important rôle in generating the baryon asymmetry. Our main observation is that composite Higgs models that include a light, gauge singlet scalar in the spectrum [as in the model based on the symmetry breaking pattern SO(6) → SO(5)], provide all necessary ingredients for viable baryogenesis. In particular, the singlet leads to a strongly first-order electroweak phase transition and introduces new sources of CP violation in dimension-five operators involving the top quark. We discuss the amountmore » of baryon asymmetry produced and the experimental constraints on the model.« less