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Title: Quark-lepton symmetry in five dimensions

Abstract

We construct a complete five dimensional quark-lepton symmetric model, with all fields propagating in the bulk. The extra dimension forms an S{sup 1}/Z{sub 2}xZ{sub 2}{sup '} orbifold with the zero mode fermions corresponding to standard model quarks localized at one fixed point. Zero modes corresponding to left (right)-chiral leptons are localized at (near) the other fixed point. This localization pattern is motivated by the symmetries of the model. Shifting the right-handed neutrinos and charged leptons slightly from the fixed point provides a new mechanism for understanding the absence of relations of the type m{sub e}=m{sub u} or m{sub e}=m{sub d} in quark-lepton symmetric models. Flavor changing neutral currents resulting from Kaluza-Klein gluon exchange, which typically arise in the quark sector of split fermion models, are suppressed due to the localization of quarks at one point. The separation of quarks and leptons in the compact extra dimension also acts to suppress the proton decay rate. This permits the extra dimension to be much larger than that obtained in a previous construct, with the bound 1/R > or approx. 30 TeV obtained.

Authors:
; ;  [1]
  1. School of Physics, Research Centre for High Energy Physics, University of Melbourne, Victoria, 3010 (Australia)
Publication Date:
OSTI Identifier:
21011111
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevD.75.045018; (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; CHIRALITY; GLUONS; KALUZA-KLEIN THEORY; MANY-DIMENSIONAL CALCULATIONS; NEUTRAL CURRENTS; NEUTRINOS; PROTONS; QUARKS; STANDARD MODEL; SYMMETRY; TEV RANGE

Citation Formats

Coulthurst, A., McDonald, K. L., and McKellar, B. H. J. Quark-lepton symmetry in five dimensions. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.045018.
Coulthurst, A., McDonald, K. L., & McKellar, B. H. J. Quark-lepton symmetry in five dimensions. United States. doi:10.1103/PHYSREVD.75.045018.
Coulthurst, A., McDonald, K. L., and McKellar, B. H. J. Thu . "Quark-lepton symmetry in five dimensions". United States. doi:10.1103/PHYSREVD.75.045018.
@article{osti_21011111,
title = {Quark-lepton symmetry in five dimensions},
author = {Coulthurst, A. and McDonald, K. L. and McKellar, B. H. J.},
abstractNote = {We construct a complete five dimensional quark-lepton symmetric model, with all fields propagating in the bulk. The extra dimension forms an S{sup 1}/Z{sub 2}xZ{sub 2}{sup '} orbifold with the zero mode fermions corresponding to standard model quarks localized at one fixed point. Zero modes corresponding to left (right)-chiral leptons are localized at (near) the other fixed point. This localization pattern is motivated by the symmetries of the model. Shifting the right-handed neutrinos and charged leptons slightly from the fixed point provides a new mechanism for understanding the absence of relations of the type m{sub e}=m{sub u} or m{sub e}=m{sub d} in quark-lepton symmetric models. Flavor changing neutral currents resulting from Kaluza-Klein gluon exchange, which typically arise in the quark sector of split fermion models, are suppressed due to the localization of quarks at one point. The separation of quarks and leptons in the compact extra dimension also acts to suppress the proton decay rate. This permits the extra dimension to be much larger than that obtained in a previous construct, with the bound 1/R > or approx. 30 TeV obtained.},
doi = {10.1103/PHYSREVD.75.045018},
journal = {Physical Review. D, Particles Fields},
number = 4,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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