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Title: Relaxing constraints from lepton flavor violation in 5D flavorful theories

Abstract

We propose new mechanisms for ameliorating the constraints on the Kaluza-Klein mass scale from charged lepton flavor violation in the framework of the standard model fields propagating in a warped extra dimension, especially in models accounting for neutrino data. These mechanisms utilize the extended five-dimensional (5D) electroweak gauge symmetry [SU(2){sub L}xSU(2){sub R}xU(1){sub X}] which is already strongly motivated in order to satisfy electroweak precision tests in this framework. We show that new choices of representations for leptons under this symmetry (naturally) can allow small mixing angles for left-handed (LH) charged leptons and simultaneously large mixing angles for their SU(2){sub L} partners, i.e., the LH neutrinos, with the neutrino data being accounted for by the latter mixings. Enhancement of charged lepton flavor violation by the large mixing angle observed in leptonic charged currents, which is present for the minimal choice of representations where the LH charged lepton and neutrino mixing angles are similar, can thus be avoided in these models. This idea might also be useful for suppressing the contributions to B{sub d,s} mixing in this framework and in order to suppress flavor violation from exchange of superpartners (instead of from KK modes) in 5D 'flavorful supersymmetry' models. Additionally, the lessmore » minimal representations can provide custodial protection for shifts in couplings of fermions to Z and, in turn, further suppress charged lepton flavor violation from tree-level Z exchange in the warped extra-dimensional scenario. As a result, {approx}O(3) TeV KK mass scale can be simultaneously consistent with charged lepton flavor violation and neutrino data, even without any particular structure in the 5D flavor parameters in the framework of a warped extra dimension.« less

Authors:
 [1]
  1. Maryland Center for Fundamental Physics, Department of Physics, University of Maryland, College Park, Maryland 20742 (United States)
Publication Date:
OSTI Identifier:
21313515
Resource Type:
Journal Article
Journal Name:
Physical Review. D, Particles Fields
Additional Journal Information:
Journal Volume: 80; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevD.80.115020; (c) 2009 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0556-2821
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CHARGED CURRENTS; COUPLING; FLAVOR MODEL; GAUGE INVARIANCE; KALUZA-KLEIN THEORY; LEPTONS; MANY-DIMENSIONAL CALCULATIONS; MASS; MIXING; NEUTRINOS; SAFETY; STANDARD MODEL; SU-2 GROUPS; SUPERSYMMETRY; TEV RANGE; U-1 GROUPS; WEINBERG ANGLE; WEINBERG-SALAM GAUGE MODEL

Citation Formats

Agashe, Kaustubh. Relaxing constraints from lepton flavor violation in 5D flavorful theories. United States: N. p., 2009. Web. doi:10.1103/PHYSREVD.80.115020.
Agashe, Kaustubh. Relaxing constraints from lepton flavor violation in 5D flavorful theories. United States. doi:10.1103/PHYSREVD.80.115020.
Agashe, Kaustubh. Tue . "Relaxing constraints from lepton flavor violation in 5D flavorful theories". United States. doi:10.1103/PHYSREVD.80.115020.
@article{osti_21313515,
title = {Relaxing constraints from lepton flavor violation in 5D flavorful theories},
author = {Agashe, Kaustubh},
abstractNote = {We propose new mechanisms for ameliorating the constraints on the Kaluza-Klein mass scale from charged lepton flavor violation in the framework of the standard model fields propagating in a warped extra dimension, especially in models accounting for neutrino data. These mechanisms utilize the extended five-dimensional (5D) electroweak gauge symmetry [SU(2){sub L}xSU(2){sub R}xU(1){sub X}] which is already strongly motivated in order to satisfy electroweak precision tests in this framework. We show that new choices of representations for leptons under this symmetry (naturally) can allow small mixing angles for left-handed (LH) charged leptons and simultaneously large mixing angles for their SU(2){sub L} partners, i.e., the LH neutrinos, with the neutrino data being accounted for by the latter mixings. Enhancement of charged lepton flavor violation by the large mixing angle observed in leptonic charged currents, which is present for the minimal choice of representations where the LH charged lepton and neutrino mixing angles are similar, can thus be avoided in these models. This idea might also be useful for suppressing the contributions to B{sub d,s} mixing in this framework and in order to suppress flavor violation from exchange of superpartners (instead of from KK modes) in 5D 'flavorful supersymmetry' models. Additionally, the less minimal representations can provide custodial protection for shifts in couplings of fermions to Z and, in turn, further suppress charged lepton flavor violation from tree-level Z exchange in the warped extra-dimensional scenario. As a result, {approx}O(3) TeV KK mass scale can be simultaneously consistent with charged lepton flavor violation and neutrino data, even without any particular structure in the 5D flavor parameters in the framework of a warped extra dimension.},
doi = {10.1103/PHYSREVD.80.115020},
journal = {Physical Review. D, Particles Fields},
issn = {0556-2821},
number = 11,
volume = 80,
place = {United States},
year = {2009},
month = {12}
}