2,252 research outputs found

### Predictions from the Fritzsch-Type Lepton Mass Matrices

We revisit the Fritzsch-type lepton mass matrix models confronted with new
experiments for neutrino mixings. It is shown that the model is viable and
leads to a rather narrow range of free parameters. Using empirical mixing
information between $\nu_e$ and $\nu_\mu$, and between $\nu_\mu$ and
$\nu_\tau$, it is predicted that the mixing angle between $nu_e$ and $\nu_\tau$
is in the range $0.04<|U_{13}|<0.20$, consistent with the CHOOZ experiment and
the lightest neutrino mass is $0.0004<m_1<0.0030$ eV. The range of the
effective mass measured in double beta decay is $0.002<0.007$ eV.Comment: Latex file with 13 pages, 6 eps file

### Burst Neutrinos from Nitrogen Flash

Neutrinos give a novel probe to explore deep interior of astrophysical
objects, which otherwise is not accessible with optical observations; among
notable examples are solar and supernova neutrinos. We show that there is a new
class of strong neutrino emission from helium burning, N + alpha --> 18F gamma
followed by beta decay 18F --> 18O + e+ + nu_e, that gives a maximum neutrino
luminosity of 10^8 times the solar bolometric luminosity at the helium-core
flash of a 1 M_sun star, whereas the flash is not observable by optical means.
This means that the neutrino flux, of average energy of 0.382 MeV, will be 10%
the solar CNO neutrino flux on Earth if the star is located at 10pc.Comment: Accepted to ApJ Letters. Replaced version with extended discussion.
Some additional references adde

### Radiative Corrections to Neutrino Reactions off Proton and Deuteron

Radiative corrections are calculated for antineutrino proton quasielastic
scattering, neutrino deuteron scattering, and the asymmetry of polarised
neutron beta decay from which $G_{A}/G_{V}$ is determined. A particular
emphasis is given to the constant parts that are usually absorbed into the
coupling constants, and thereby those that appear in the processes that concern
us are unambiguously tied among each other.Comment: Talk give at the 10th International Symposium on Particles, Strings
and Cosmology (at Northeastern University, Boston, August 16-22, 2004

### Megaton Water Cerenkov Detectors and Astrophysical Neutrinos

Although formal proposals have not yet been made, the UNO and
Hyper-Kamiokande projects are being developed to follow-up the tremendously
successful program at Super-Kamiokande using a detector that is 20-50 times
larger. The potential of such a detector to continue the study of astrophysical
neutrinos is considered and contrasted with the program for cubic kilometer
neutrino observatories.Comment: 4 pages Submitted to the Proceedings of the 2004 Neutrino Oscillation
Workshop, Otranto Ital

### A Derivation of the Fermi Function in Perturbative Quantum Field Theory

We postulate that the Fermi function should be derived from the amplitude,
not from the solution of the Dirac equation, in the quantum field theory.
Then, we obtain the following results.
1, We give the amplitude and the width of the neutron beta decay, $n \to p +
e^- + \bar \nu_e$ to one loop order. It is carried out by the Feynman
parameter integration.
2, As the result, we find the terms which can be interpreted as the Fermi
function expanded to order $\alpha$.
3, We also give the same result using complex analysis.
4, We check that there are no such terms in the similar process, $\bar \nu_e
+ p \to e^+ + n$.
5, We perform the Fermi function expanded to order $\alpha^2$ using complex
analysis.Comment: 8 page

### Finite-Size Effect of Hadron Masses with Kogut-Susskind Quarks

We present numerical results and their analyses of finite-size effects of
hadron masses for both quenched and full QCD calculations. We show that they
are much larger for full QCD due to dynamical sea quarks and the associated
breaking of $Z(3)$ symmetry. We also argue that finite-size effects are
non-negligible even for the largest lattice size simulation currently being
made for a very small quark mass. (talk at lattice93)Comment: 4 pages, compressed, uuencoded PostScript file(name:lat93.ps.Z

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