2,084 research outputs found
Neutrino Helioseismology
The observed deficit of solar neutrinos may call for an improved
standard model of the sun or an expanded standard model of particle physics
({\it e.g.,} with neutrino masses and mixing). In the former case, contemporary
fluid motions and thermal fluctuations in the sun's core may modify nuclear
reaction rates and restore agreement. To test this notion, we propose a search
for short--term variations of the solar neutrino flux.Comment: 4 pages, HUTP-92/A03
Muonium-Antimuonium Oscillations in an extended Minimal Supersymmetric Standard Model with right-handed neutrinos
The electron and muon number violating muonium-antimuonium oscillation
process in an extended Minimal Supersymmetric Standard Model is investigated.
The Minimal Supersymmetric Standard Model is modified by the inclusion of three
right-handed neutrino superfields. While the model allows the neutrino mass
terms to mix among the different generations, the sneutrino and slepton mass
terms have only intra-generation lepton number violation but not
inter-generation lepton number mixing. So doing, the muonium-antimuonium
conversion can then be used to constrain those model parameters which avoid
further constraint from the decay bounds. For a wide range of
parameter values, the contributions to the muonium-antimuonium oscillation time
scale are at least two orders of magnitude below the sensivity of current
experiments. However, if the ratio of the two Higgs field VEVs, , is
very small, there is a limited possibility that the contributions are large
enough for the present experimental limit to provide an inequality relating
with the light neutrino mass scale which is generated by
see-saw mechanism. The resultant lower bound on as a function of
is more stringent than the analogous bounds arising from the muon and
electron anomalous magnetic moments as computed using this model.Comment: 29 pages, 7 figures, 3 tables, Late
The Frobenius group T13 and the canonical see-saw mechanism applied to neutrino mixing
The compatibility of the Frobenius group T13 with the canonical see-saw
mechanism of neutrino mixing is examined. The Standard Model is extended in a
minimalist way, by introducing a family symmetry and three right-handed
neutrinos. To fit experiments and place constraints on the possibilities,
tribimaximal mixing is used as a guideline. The application of both a family
symmetry group and the canonical see-saw mechanism naturally generates small
neutrino masses. The various possibilities from combining these two models are
listed. Enough constraints are produced to narrow down the parameters of the
neutrino mass matrix to two. This is therefore a predictive model where
neutrino mass eigenvalues and allowed regions for neutrinoless double beta
decay are suggested.Comment: Accepted for publication in Physical Review D. 13 page
Quark-lepton symmetry and complementarity
We argue that the difference between the observed approximate quark-lepton
complementarity and the theoretical prediction based on realistic quark-lepton
symmetry within the seesaw mechanism may be adjusted by means of a triplet
contribution in the seesaw formula.Comment: 7 pages, RevTex
Tri-N-ification
We consider a natural generalization of trinification to theories with 3N
SU(3) gauge groups. These theories have a simple moose representation and a
gauge boson spectrum that can be interpreted via the deconstruction of a 5D
theory with unified symmetry broken on a boundary. Although the matter and
Higgs sectors of the theory have no simple extra-dimensional analog, gauge
unification retains features characteristic of the 5D theory. We determine
possible assignments of the matter and Higgs fields to unified multiplets and
present theories that are viable alternatives to minimal trinified GUTs.Comment: 21 pages LaTeX, 6 eps figure
The mass of the Higgs boson in the trinification subgroup of E6
The extension of the standard model to SU(3)_L x SU(3)_R x SU(3)_C is
considered. Spontaneous symmetry breaking requires two Higgs field multiplets
with a strong hierarchical structure of vacuum expectation values. These vacuum
expectation values, some of them known from experiment, are used to construct
invariant potentials in form of a sum of individual potentials relevant at the
weak scale. As in a previous suggestion one may normalize the most important
individual potentials such that their mass eigenvalues agree with their very
large vacuum expectation values. In this case (for a wide class of parameters)
the scalar field corresponding to the standard model Higgs turns out to have
the precise mass value m_Higgs = v/sqrt(2) = 123 GeV at the weak scale. The
physical mass (pole mass) is larger and found to be 125 +/- 1.4 GeV.Comment: 5 pages, version appearing in Phys. Rev.
Yang-Mills theory for non-semisimple groups
For semisimple groups, possibly multiplied by U(1)'s, the number of
Yang-Mills gauge fields is equal to the number of generators of the group. In
this paper, it is shown that, for non-semisimple groups, the number of
Yang-Mills fields can be larger. These additional Yang-Mills fields are not
irrelevant because they appear in the gauge transformations of the original
Yang-Mills fields. Such non-semisimple Yang-Mills theories may lead to physical
consequences worth studying. The non-semisimple group with only two generators
that do not commute is studied in detail.Comment: 16 pages, no figures, prepared with ReVTeX
The effect of supersymmetry breaking in the Mass Varying Neutrinos
We discuss the effect of the supersymmetry breaking on the Mass Varying
Neutrinos(MaVaNs) scenario. Especially, the effect mediated by the
gravitational interaction between the hidden sector and the dark energy sector
is studied. A model including a chiral superfield in the dark sector and the
right handed neutrino superfield is proposed. Evolutions of the neutrino mass
and the equation of state parameter are presented in the model. It is remarked
that only the mass of a sterile neutrino is variable in the case of the
vanishing mixing between the left-handed and a sterile neutrino on cosmological
time scale. The finite mixing makes the mass of the left-handed neutrino
variable.Comment: 6 pages, 7 figures, RevTeX4, references added, discussions and
figures revise
Minimal Seesaw as an Ultraviolet Insensitive Cure for the Problems of Anomaly Mediation
We show that an intermediate scale supersymmetric left-right seesaw scenario
with automatic R-parity conservation can cure the problem of tachyonic slepton
masses that arises when supersymmetry is broken by anomaly mediation, while
preserving ultraviolet insensitivity. The reason for this is the existence of
light B - L = 2 higgses with yukawa couplings to the charged leptons. We find
these theories to have distinct predictions compared to the usual mSUGRA and
gauge mediated models as well as the minimal AMSB models. Such predictions
include a condensed gaugino mass spectrum and possibly a correspondingly
condensed sfermion spectrum.Comment: 19 pages, 1 figur
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