22,288 research outputs found
A novel and economical explanation for SM fermion masses and mixings
I propose the first multiscalar singlet extension of the Standard Model (SM),
that generates tree level top quark and exotic fermion masses as well as one
and three loop level masses for charged fermions lighter than the top quark and
for light active neutrinos, respectively, without invoking electrically charged
scalar fields. That model, which is based on the discrete
symmetry, successfully explains the observed SM fermion mass and mixing
pattern. The charged exotic fermions induce one loop level masses for charged
fermions lighter than the top quark. The charged scalar singlet
generates the observed charged fermion mass and quark mixing pattern.Comment: 4 pages. Section on the 750 GeV diphoton anomaly removed. Accepted
for publication as a Letter in the European Physical Journal
A predictive model with flavour symmetry
We propose a predictive model based on the gauge group supplemented by the discrete group, which successfully describes
the SM fermion mass and mixing pattern. The small active neutrino masses are
generated via inverse seesaw mechanism with three very light Majorana
neutrinos. The observed charged fermion mass hierarchy and quark mixing pattern
are originated from the breaking of the
discrete group at very high scale. The obtained values for the physical
observables for both quark and lepton sectors are in excellent agreement with
the experimental data. The model predicts a vanishing leptonic Dirac CP
violating phase as well as an effective Majorana neutrino mass parameter of
neutrinoless double beta decay, with values 2 and 48 meV
for the normal and the inverted neutrino mass hierarchies, respectively.Comment: 20 pages. Final version published in Nuclear Physics
Fermion mass and mixing pattern in a minimal T7 flavor 331 model
We present a model based on the
gauge symmetry having an extra
flavor group, which successfully describes the observed SM fermion mass and
mixing pattern. In this framework, the light active neutrino masses arise via
double seesaw mechanism and the observed charged fermion mass and quark mixing
hierarchy is a consequence of the symmetry
breaking at very high energy. In our minimal flavor 331 model, the
spectrum of neutrinos includes very light active neutrinos as well as heavy and
very heavy sterile neutrinos. The model has in total 16 effective free
parameters, which are fitted to reproduce the experimental values of the 18
physical observables in the quark and lepton sectors. The obtained physical
observables for both quark and lepton sectors are compatible with their
experimental values. The model predicts the effective Majorana neutrino mass
parameter of neutrinoless double beta decay to be 3 and
40 meV for the normal and the inverted neutrino spectrum, respectively.
Furthermore, our model features a vanishing leptonic Dirac CP violating phase.Comment: 18 pages. Final version. To be published in Journal of Physics G.
arXiv admin note: substantial text overlap with arXiv:1309.656
Littlest Inverse Seesaw Model
We propose a minimal predictive inverse seesaw model based on two
right-handed neutrinos and two additional singlets, leading to the same low
energy neutrino mass matrix as in the Littlest Seesaw (LS) (type I) model. In
order to implement such a Littlest Inverse Seesaw (LIS) model, we have used an
family symmetry, together with other various symmetries, flavons and
driving fields. The resulting LIS model leads to an excellent fit to the low
energy neutrino parameters, including the prediction of a normal neutrino mass
ordering, exactly as in the usual LS model. However, unlike the LS model, the
LIS model allows charged lepton flavour violating (CLFV) processes and lepton
conversion in nuclei within reach of the forthcoming experiments.Comment: 17 pages, 9 figures. Published versio
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