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Title: Fermion masses and mixings from heterotic orbifold models

Abstract

We search for a possibility of getting realistic fermion mass ratios and mixing angles from renormalizable couplings on the Z6-I heterotic orbifold with one pair of Higgs doublets. In the quark sector, we find cases with reasonable results if we ignore the first family. In the lepton sector, we can fit the charged lepton mass ratios, the neutrino mass squared difference ratio, and the lepton mixing angles, considering all three families00.

Authors:
 [1]
  1. School of Physics, KIAS, Cheongnyangni-dong, Seoul 130-722 (Korea, Republic of)
Publication Date:
OSTI Identifier:
20729186
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 805; Journal Issue: 1; Conference: PASCOS 2005: 11. international symposium on particles, strings, and cosmology, Gyeongju (Korea, Republic of), 30 May - 4 Jun 2005; Other Information: DOI: 10.1063/1.2149724; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; HIGGS BOSONS; HIGGS MODEL; MIXING; NEUTRINOS; QUANTUM FIELD THEORY; QUARKS; RENORMALIZATION; REST MASS; SUPERSTRING MODELS; WEINBERG ANGLE

Citation Formats

Park, Jae-hyeon. Fermion masses and mixings from heterotic orbifold models. United States: N. p., 2005. Web. doi:10.1063/1.2149724.
Park, Jae-hyeon. Fermion masses and mixings from heterotic orbifold models. United States. doi:10.1063/1.2149724.
Park, Jae-hyeon. Fri . "Fermion masses and mixings from heterotic orbifold models". United States. doi:10.1063/1.2149724.
@article{osti_20729186,
title = {Fermion masses and mixings from heterotic orbifold models},
author = {Park, Jae-hyeon},
abstractNote = {We search for a possibility of getting realistic fermion mass ratios and mixing angles from renormalizable couplings on the Z6-I heterotic orbifold with one pair of Higgs doublets. In the quark sector, we find cases with reasonable results if we ignore the first family. In the lepton sector, we can fit the charged lepton mass ratios, the neutrino mass squared difference ratio, and the lepton mixing angles, considering all three families00.},
doi = {10.1063/1.2149724},
journal = {AIP Conference Proceedings},
number = 1,
volume = 805,
place = {United States},
year = {Fri Dec 02 00:00:00 EST 2005},
month = {Fri Dec 02 00:00:00 EST 2005}
}
  • We systematically study the possibility for realizing realistic values of lepton mass ratios and mixing angles by using only renormalizable Yukawa couplings derived from the heterotic Z{sub 6}-I orbifold. We assume one pair of up and down sector Higgs fields. We consider both the Dirac neutrino mass scenario and the seesaw scenario with degenerate right-handed majorana neutrino masses. It is found that realistic values of the charged lepton mass ratios, m{sub e}/m{sub {tau}} and m{sub {mu}}/m{sub {tau}}, the neutrino mass squared difference ratio, {delta}m{sub 31}{sup 2}/{delta}m{sub 21}{sup 2}, and the lepton mixing angles can be obtained in certain cases.
  • We present a detailed study of the quark and lepton mass spectra in a SO(10) framework with one 10{sub H} and one 126{sub H} Higgs representations in the Yukawa sector. We consider in full generality the interplay between type I and type II seesaw for neutrino masses. We first perform a {chi}{sup 2} fit of fermion masses independent on the structure of the GUT Higgs potential and determine the regions of the parameter space that are preferred by the fermion mass sum rules. We then apply our study to the case of the minimal renormalizable SUSY SO(10) GUT with onemore » 10{sub H}, one 126{sub H}, one 126{sub H}, and one 210{sub H} Higgs representations. By requiring that proton decay bounds are fulfilled we identify a very limited area in the parameter space where all fermion data are consistently reproduced. We find that in all cases gauge coupling unification in the supersymmetric scenario turns out to be severely affected by the presence of lighter than GUT (albeit B-L conserving) states. We then conclusively show that the minimal supersymmetric SO(10) scenario here considered is not consistent with data. The fit of neutrino masses with type I and type II seesaws within a renormalizable SO(10) framework strongly suggests a non-SUSY scenario for gauge unification.« less
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