148 research outputs found
Neutrino Interactions In Oscillation Experiments
We calculate neutrino induced cross-sections relevant for oscillation
experiments, including the -lepton threshold for quasi-elastic, resonance
and deep inelastic scattering. In addition to threshold effects, we include
nuclear corrections for heavy targets which are moderate for quasi-elastic and
large for single pion production. Nuclear effects for deep inelastic reactions
are small. We present cross sections together with their nuclear corrections
for various channels which are useful for interpreting the experimental results
and for determining parameters of the neutrino sector..Comment: 24 pages, 18 figure
Quantum Isometries of the finite noncommutative geometry of the Standard Model
We compute the quantum isometry group of the finite noncommutative geometry F
describing the internal degrees of freedom in the Standard Model of particle
physics. We show that this provides genuine quantum symmetries of the spectral
triple corresponding to M x F where M is a compact spin manifold. We also prove
that the bosonic and fermionic part of the spectral action are preserved by
these symmetries.Comment: 29 pages, no figures v3: minor change
Leptogenesis in a Realistic Supersymmetric Model of Inflation with a Low Reheat Temperature
We discuss leptogenesis in a realistic supersymmetric model of inflation with
a low reheat temperature 1-10 GeV. The lepton asymmetry is generated by a
decaying right handed sneutrino, which is produced after inflation during
preheating. The inflationary model is based on a simple variant of the
Next-to-Minimal Supersymmetric Standard model (NMSSM) which solves the \mu
problem, called \phiNMSSM, where the additional singlet \phi plays the role of
the inflaton in hybrid (or inverted hybrid) type models. The model is invariant
under an approximate Peccei-Quinn symmetry which also solves the strong CP
problem, and leads to an invisible axion with interesting cosmological
consequences. We show how the baryon number of the universe and the nature of
cold dark matter are determined by the same parameters controlling the strong
CP problem, the \mu problem and the neutrino masses and mixing angles.Comment: 17 page, latex, 1 eps fi
New results of 116Cd double beta decay study with 116CdWO4 scintillators
A new phase of 116Cd double beta decay experiment is in progress in the
Solotvina Underground Laboratory. Four enriched 116CdWO4 scintillators with
total mass 339 g are used in a set up, whose active shield is made of 15
natural CdWO4 crystals (20.6 kg). The background rate in the energy interval
2.5-3.2 MeV is 0.03 counts/y*kg*keV. The half-life for 2-neutrino 2-beta decay
of 116Cd is measured as T{1/2}(2-neutrino) =
[2.6+-0.1(stat)-0.4+0.7}(syst)]*10**19 y. The T{1/2} limits for neutrinoless
2-beta decay of 116Cd are set as T{1/2} >= 0.7(2.5)*10**23 y at 90%(68%) C.L.
for transition to ground state of 116Sn, while for decays to the first 2+ and
second 0+ excited levels of 116Sn as T{1/2}>=1.3(4.8)*10**22 y and
>=0.7(2.4)*10**22 y with 90%(68%) C.L., respectively. For 0-neutrino 2-beta
decay with emission of one or two Majorons, the limits are T{1/2}(0-neutrino
M1) >=3.7(5.8)*10**21 y and T{1/2}(0-neutrino M2)>=5.9(9.4)*10**20 y at
90%(68%) C.L. Restrictions on the value of the neutrino mass, right-handed
admixtures in the weak interaction, and the neutrino-Majoron coupling constant
are derived as: m(neutrino)<=2.6(1.4) eV, eta <=3.9*10**-8, lambda
<=3.4*10**-6, and g{M}<= 12(9.5)*10**-5 at 90%(68%) C.L., respectively.Comment: 28 pages, 9 figures (LaTeX). Phys. Rev. C (in press
Neutrino Oscillations in a Predictive SUSY GUT
In this letter we present a predictive SO(10) SUSY GUT with flavor symmetry
U(2) \times U(1) which has several nice features. We are able to fit fermion
masses and mixing angles, including recent neutrino data, with 9 parameters in
the charged fermion sector and 4 in the neutrino sector. The flavor symmetry
plays a preeminent role -- (i) The model is "natural" -- we include all terms
allowed by the symmetry. It restricts the number of arbitrary parameters and
enforces many zeros in the effective mass matrices. (ii) Flavor symmetry
breaking from U(2) \times U(1) \to U(1) \to nothing generates the family
hierarchy. It also constrains squark and slepton mass matrices, thus
ameliorating flavor violation resulting from squark and slepton loop
contributions. (iii) Finally, it naturally gives large angle mixing describing atmospheric neutrino oscillation data and small
angle mixing consistent with the small mixing angle MSW
solution to solar neutrino data
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