Leptonnumber violation and righthanded 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 symmetrybreaking 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 powercounting, as in chiral perturbation theory. A hierarchy of leptonnumber violating effects follows. Leading corrections to the SM are nonoblique. The effective theory includes stable light righthanded 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:
 IFIC, Departament de Fisica Teorica, CSIC  Universitat de Valencia, Edifici d'Instituts de Paterna, Apt. Correus 22085, 46071 Valencia (Spain)
 Groupe Physique Theorique, Unite mixte de recherche 8608 du CNRS, IPN Orsay, Universite ParisSud 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; SU2 GROUPS; SYMMETRY BREAKING; U1 GROUPS; UNITARY SYMMETRY
Citation Formats
Hirn, Johannes, and Stern, Jan. Leptonnumber violation and righthanded neutrinos in Higgsless effective theories. United States: N. p., 2006.
Web. doi:10.1103/PhysRevD.73.056001.
Hirn, Johannes, & Stern, Jan. Leptonnumber violation and righthanded neutrinos in Higgsless effective theories. United States. doi:10.1103/PhysRevD.73.056001.
Hirn, Johannes, and Stern, Jan. Wed .
"Leptonnumber violation and righthanded neutrinos in Higgsless effective theories". United States.
doi:10.1103/PhysRevD.73.056001.
@article{osti_20776905,
title = {Leptonnumber violation and righthanded 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 symmetrybreaking 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 powercounting, as in chiral perturbation theory. A hierarchy of leptonnumber violating effects follows. Leading corrections to the SM are nonoblique. The effective theory includes stable light righthanded 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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