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Title: Lepton-number violation and right-handed neutrinos in Higgsless effective theories

Abstract

Following previous work, we identify a symmetry S{sub nat} that generalizes the concept of custodial symmetry, keeping under control deviations from the standard model (SM). To realize S{sub nat} linearly, the space of gauge fields has to be extended. Covariant constraints formulated in terms of spurions reduce S{sub nat} back to SU(2){sub L}xU(1){sub Y}. This allows for a covariant introduction of explicit S{sub nat}-breaking parameters. We assume that S{sub nat} is at play in a theory of electroweak symmetry-breaking without a light Higgs particle. We describe some consequences of this assumption, using a nondecoupling effective theory in which the loop expansion procedure is based on both momentum and spurion power-counting, as in chiral perturbation theory. A hierarchy of lepton-number violating effects follows. Leading corrections to the SM are nonoblique. The effective theory includes stable light right-handed neutrinos, with an unbroken Z{sub 2} symmetry forbidding neutrino Dirac masses. {nu}{sub R} contribution to dark matter places bounds on their masses.

Authors:
 [1];  [2]
  1. IFIC, Departament de Fisica Teorica, CSIC - Universitat de Valencia, Edifici d'Instituts de Paterna, Apt. Correus 22085, 46071 Valencia (Spain)
  2. Groupe Physique Theorique, Unite mixte de recherche 8608 du CNRS, IPN Orsay, Universite Paris-Sud XI, 91406 Orsay (France)
Publication Date:
OSTI Identifier:
20776905
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevD.73.056001; (c) 2006 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; CHIRAL SYMMETRY; CHIRALITY; CORRECTIONS; HIGGS BOSONS; HIGGS MODEL; LEPTON NUMBER; NEUTRINOS; NONLUMINOUS MATTER; PERTURBATION THEORY; REST MASS; SPURIONS; STANDARD MODEL; SU-2 GROUPS; SYMMETRY BREAKING; U-1 GROUPS; UNITARY SYMMETRY

Citation Formats

Hirn, Johannes, and Stern, Jan. Lepton-number violation and right-handed neutrinos in Higgsless effective theories. United States: N. p., 2006. Web. doi:10.1103/PhysRevD.73.056001.
Hirn, Johannes, & Stern, Jan. Lepton-number violation and right-handed neutrinos in Higgsless effective theories. United States. doi:10.1103/PhysRevD.73.056001.
Hirn, Johannes, and Stern, Jan. Wed . "Lepton-number violation and right-handed neutrinos in Higgsless effective theories". United States. doi:10.1103/PhysRevD.73.056001.
@article{osti_20776905,
title = {Lepton-number violation and right-handed neutrinos in Higgsless effective theories},
author = {Hirn, Johannes and Stern, Jan},
abstractNote = {Following previous work, we identify a symmetry S{sub nat} that generalizes the concept of custodial symmetry, keeping under control deviations from the standard model (SM). To realize S{sub nat} linearly, the space of gauge fields has to be extended. Covariant constraints formulated in terms of spurions reduce S{sub nat} back to SU(2){sub L}xU(1){sub Y}. This allows for a covariant introduction of explicit S{sub nat}-breaking parameters. We assume that S{sub nat} is at play in a theory of electroweak symmetry-breaking without a light Higgs particle. We describe some consequences of this assumption, using a nondecoupling effective theory in which the loop expansion procedure is based on both momentum and spurion power-counting, as in chiral perturbation theory. A hierarchy of lepton-number violating effects follows. Leading corrections to the SM are nonoblique. The effective theory includes stable light right-handed neutrinos, with an unbroken Z{sub 2} symmetry forbidding neutrino Dirac masses. {nu}{sub R} contribution to dark matter places bounds on their masses.},
doi = {10.1103/PhysRevD.73.056001},
journal = {Physical Review. D, Particles Fields},
number = 5,
volume = 73,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2006},
month = {Wed Mar 01 00:00:00 EST 2006}
}
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