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Title: Discrete minimal flavor violation

Abstract

We investigate the consequences of replacing the global flavor symmetry of minimal flavor violation (MFV) SU(3){sub Q}xSU(3){sub U}xSU(3){sub D}x{center_dot}{center_dot}{center_dot} by a discrete D{sub Q}xD{sub U}xD{sub D}x{center_dot}{center_dot}{center_dot} symmetry. Goldstone bosons resulting from the breaking of the flavor symmetry generically lead to bounds on new flavor structure many orders of magnitude above the TeV scale. The absence of Goldstone bosons for discrete symmetries constitute the primary motivation of our work. Less symmetry implies further invariants and renders the mass-flavor basis transformation observable in principle and calls for a hierarchy in the Yukawa matrix expansion. We show, through the dimension of the representations, that the (discrete) symmetry in principle does allow for additional {delta}F=2 operators. If though the {delta}F=2 transitions are generated by two subsequent {delta}F=1 processes, as, for example, in the standard model, then the four crystal-like groups {sigma}(168){approx_equal}PSL(2,F{sub 7}), {sigma}(72{phi}), {sigma}(216{phi}) and especially {sigma}(360{phi}) do provide enough protection for a TeV-scale discrete MFV scenario. Models where this is not the case have to be investigated case by case. Interestingly {sigma}(216{phi}) has a (nonfaithful) representation corresponding to an A{sub 4} symmetry. Moreover we argue that the, apparently often omitted, (D) groups are subgroups of an appropriate {delta}(6g{sup 2}). We would like tomore » stress that we do not provide an actual model that realizes the MFV scenario nor any other theory of flavor.« less

Authors:
 [1];  [2]
  1. School of Physics and Astronomy, University of Southampton Highfield, Southampton SO17 1BJ (United Kingdom)
  2. School of Engineering, University of Southampton Highfield, Southampton SO17 1BJ (United Kingdom)
Publication Date:
OSTI Identifier:
21325290
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 80; Journal Issue: 7; Other Information: DOI: 10.1103/PhysRevD.80.076009; (c) 2009 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; CRYSTALS; EXPANSION; FLAVOR MODEL; GOLDSTONE BOSONS; MASS; STANDARD MODEL; SU-3 GROUPS; SYMMETRY; SYMMETRY BREAKING; TEV RANGE; TRANSFORMATIONS; U GROUPS

Citation Formats

Zwicky, Roman, and Fischbacher, Thomas. Discrete minimal flavor violation. United States: N. p., 2009. Web. doi:10.1103/PHYSREVD.80.076009.
Zwicky, Roman, & Fischbacher, Thomas. Discrete minimal flavor violation. United States. doi:10.1103/PHYSREVD.80.076009.
Zwicky, Roman, and Fischbacher, Thomas. 2009. "Discrete minimal flavor violation". United States. doi:10.1103/PHYSREVD.80.076009.
@article{osti_21325290,
title = {Discrete minimal flavor violation},
author = {Zwicky, Roman and Fischbacher, Thomas},
abstractNote = {We investigate the consequences of replacing the global flavor symmetry of minimal flavor violation (MFV) SU(3){sub Q}xSU(3){sub U}xSU(3){sub D}x{center_dot}{center_dot}{center_dot} by a discrete D{sub Q}xD{sub U}xD{sub D}x{center_dot}{center_dot}{center_dot} symmetry. Goldstone bosons resulting from the breaking of the flavor symmetry generically lead to bounds on new flavor structure many orders of magnitude above the TeV scale. The absence of Goldstone bosons for discrete symmetries constitute the primary motivation of our work. Less symmetry implies further invariants and renders the mass-flavor basis transformation observable in principle and calls for a hierarchy in the Yukawa matrix expansion. We show, through the dimension of the representations, that the (discrete) symmetry in principle does allow for additional {delta}F=2 operators. If though the {delta}F=2 transitions are generated by two subsequent {delta}F=1 processes, as, for example, in the standard model, then the four crystal-like groups {sigma}(168){approx_equal}PSL(2,F{sub 7}), {sigma}(72{phi}), {sigma}(216{phi}) and especially {sigma}(360{phi}) do provide enough protection for a TeV-scale discrete MFV scenario. Models where this is not the case have to be investigated case by case. Interestingly {sigma}(216{phi}) has a (nonfaithful) representation corresponding to an A{sub 4} symmetry. Moreover we argue that the, apparently often omitted, (D) groups are subgroups of an appropriate {delta}(6g{sup 2}). We would like to stress that we do not provide an actual model that realizes the MFV scenario nor any other theory of flavor.},
doi = {10.1103/PHYSREVD.80.076009},
journal = {Physical Review. D, Particles Fields},
number = 7,
volume = 80,
place = {United States},
year = 2009,
month =
}
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