65 research outputs found
Unifying flipped SU(5) in five dimensions
It is shown that embedding a four-dimensional flipped SU(5) model in a
five-dimensional SO(10) model, preserves the best features of both flipped
SU(5) and SO(10). The missing partner mechanism, which naturally achieves both
doublet-triplet splitting and suppression of d=5 proton decay operators, is
realized as in flipped SU(5), while the gauge couplings are unified as in
SO(10). The masses of down quarks and charged leptons, which are independent in
flipped SU(5), are related by the SO(10). Distinctive patterns of quark and
lepton masses can result. The gaugino mass M_1 is independent of M_3 and M_2,
which are predicted to be equal.Comment: revised version-to appear in PRD, 23 pages, 3 figures, ReVTeX
Flipping SU(5) Towards Five Dimensional Unification
It is shown that embedding of flipped SU(5) in a five-dimensional SO(10)
enables exact unification of the gauge coupling constants. The demand for the
unification uniquely determines both the compactification scale and the cutoff
scale. These are found to be 5.5 \times 10^{14} GeV and 1.0 \times 10^{17} GeV
respectively. The theory explains the absence of d=5 proton-decay operators
through the implementation of the missing partner mechanism. On the other hand,
the presence of d=6 proton-decay operators points towards the bulk localization
of the first and the second family of matter fields.Comment: 21 pages, references added, 3 Postscript figures, ReVTeX
Leptogenesis and Neutrino Oscillations Within A Predictive G(224)/SO(10)-Framework
A framework based on an effective symmetry that is either G(224)= SU(2)_L x
SU(2)_R xSU(4)^c or SO(10) has been proposed (a few years ago) that
successfully describes the masses and mixings of all fermions including
neutrinos, with seven predictions, in good accord with the data. Baryogenesis
via leptogenesis is considered within this framework by allowing for natural
phases (~ 1/20-1/2) in the entries of the Dirac and Majorana mass-matrices. It
is shown that the framework leads quite naturally, for both thermal as well as
non-thermal leptogenesis, to the desired magnitude for the baryon asymmetry.
This result is obtained in full accord with the observed features of the
atmospheric and solar neutrino oscillations, as well as with those of the quark
and charged lepton masses and mixings, and the gravitino-constraint. Hereby one
obtains a unified description of fermion masses, neutrino oscillations and
baryogenesis (via leptogenesis) within a single predictive framework.Comment: Efficiency factor updated, some clarifications and new references
added. 19 page
B decays and models for CP violation
The decay modes to , , , and
are promising channels to study the unitarity triangle of the CP violating CKM
matrix. In this paper I study the consequences of these measurements in the
Weinberg model. I show that using the same set of measurements, the following
different mechanisms for CP violation can be distinguished: 1) CP is violated
in the CKM sector only; 2) CP is violated spontaneously in the Higgs sector
only; And 3) CP is violated in both the CKM and Higgs sectors.Comment: 18 pagers, Revtex, Four compressed figures. Some typos in the figure
captions are correcte
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Comportamento ingestivo de cabras Alpinas em lactação alimentadas com dietas contendo diferentes níveis de fibra em detergente neutro proveniente da forragem
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Comportamento ingestivo diurno de novilhos Nelore recebendo níveis crescentes de suplementação em pastejo de capim-braquiária
Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE) Conceptual Design Report Volume 2: The Physics Program for DUNE at LBNF
The Physics Program for the Deep Underground Neutrino Experiment (DUNE) at the Fermilab Long-Baseline Neutrino Facility (LBNF) is described
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