2,493 research outputs found
Neutrino oscillations and neutrinoless double-beta decay
We consider the scheme with mixing of three neutrinos and a mass hierarchy.
We shown that, under the natural assumptions that massive neutrinos are
Majorana particles and there are no unlikely fine-tuned cancellations among the
contributions of the different neutrino masses, the results of solar neutrino
experiments imply a lower bound for the effective Majorana mass in neutrinoless
double-beta decay. We also discuss briefly neutrinoless double-beta decay in
schemes with mixing of four neutrinos. We show that one of them is favored by
the data.Comment: 7 pages. Presented at TAUP'99, 6-10 September 1999, College de
France, Paris, Franc
Implications of CHOOZ results for the decoupling of solar and atmospheric neutrino oscillations
We have considered the results of solar and atmospheric neutrino oscillation
experiments in the scheme of mixing of three neutrinos with a mass hierarchy.
It is shown that the recent results of the CHOOZ experiment imply that
|U_{e3}|^2<<1 (U is the neutrino mixing matrix), that the oscillations of solar
neutrinos are described by the two-generation formalism and that the
oscillations of solar and atmospheric neutrinos decouple. It is also shown that
if not only |U_{e3}|^2<<1 but also |U_{e3}|<<1, then the oscillations of
atmospheric neutrinos do not depend on matter effects and are described by the
two-generation formalism. In this case, with an appropriate identification of
the mixing parameters, the two-generation analyses of solar and atmospheric
neutrino data provide direct information on the mixing parameters of three
neutrinos. We discuss the possibility to get information on |U_{e3}|^2 in
long-baseline neutrino oscillation experiments.Comment: 12 pages, no figure
Possible tests for sterile neutrinos
It is shown that the future SNO and Super-Kamiokande experiments, in which
high energy neutrinos will be detected through the observation
of CC, NC and -- elastic scattering processes, could allow to reveal in
a model independent way the presence of sterile neutrinos in the flux of solar
neutrinos on the earth.Comment: Latex file, 6 pages including 1 figure. The postscript file of text
and figures is available at http://www.to.infn.it/teorici/giunti/papers.html
or ftp://ftp.to.infn.it/pub/giunti/1995/dftt-84-95/dftt-84-95.p
Neutrino Mixing and Future Solar Neutrino Experiments
Possibilities of a model independent treatment of the data from future
real-time solar neutrino experiments (SNO, Super-Kamiokande and others) are
discussed. It is shown that in the general case of transitions of the initial
solar 's into and/or the total flux of initial 8B
neutrinos and the survival probability can be determined directly from
the experimental data. Lower bounds for the probability of transition of solar
's into all possible sterile states are derived and expressed through
measurable quantities.Comment: 3 pages. Compressed postscript file. If you prefer the uncompressed
postscript file or a hardcopy of the paper, please write to
[email protected]. Talk presented by S.M. Bilenky at TAUP93. DFTT 66/9
Four-Neutrino Scenarios
The main features of four-neutrino 3+1 and 2+2 mixing schemes are reviewed,
after a discussion on the necessity of at least four massive neutrinos if the
solar, atmospheric and LSND anomalies are due to neutrino oscillations.
Complete list of references on four-neutrino mixing at
http://www.to.infn.it/~giunti/neutrinoComment: 7 pages. Talk presented at NOW 2000, Conca Specchiulla (Otranto,
Italy), 9-16 Sep. 200
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