21,554 research outputs found
Neutrino Masses and Mixing: Where We Stand and Where We are Going
In this talk I review our present knowledge on neutrino masses and mixing as
well as the expectations from near future experiments.Comment: 19 Pages, 11 figures. Review talk given at the 10th International
Conference on Supersymmetry and Unification of Fundamental Interactions,
SUSY02 (June 17-23, 2002, DESY, Hamburg
Impact of two mass-scale oscillations on the analysis of atmospheric and reactor neutrino data
We study the stability of the results of 3-nu oscillation analysis of
atmospheric and reactor neutrino data under departures of the one--dominant
mass scale approximation. In order to do so we perform the analysis of
atmospheric and reactor neutrino data in terms of three--neutrino oscillations
where the effect of both mass differences is explicitly considered. We study
the allowed parameter space resulting from this analysis as a function of the
mass splitting hierarchy parameter alpha = Delta m^2/Delta M^2 which
parametrizes the departure from the one--dominant mass scale approximation. We
consider schemes with both direct and inverted mass ordering. Our results show
that in the analysis of atmospheric data the derived range of the largest mass
splitting, Delta M^2$, is stable while the allowed ranges of mixing angles
sin^2 theta_{23} and sin^2 theta_{13} are wider than those obtained in the
one--dominant mass scale approximation. Inclusion of the CHOOZ reactor data in
the analysis results into the reduction of the parameter space in particular
for the mixing angles. As a consequence the final allowed ranges of parameters
from the combined analysis are only slightly broader than when obtained in the
one--dominant mass scale approximation.Comment: Updated data, references added and typos corrected. Version to appear
in Eur.Phys.J.
Status of Global Analysis of Neutrino Oscillation Data
In this talk we discuss some details of the analysis of neutrino data and our
present understanding of neutrino masses and mixing. This talk is based on
hep-ph/0306001, hep-ph/0306226 and hep-ph/0404085.Comment: 10 pages, LaTeX file using ws-procs9x6, 6 figures included. Talk
given by MCGG at the 5th Workshop on "Neutrino Oscillations and their Origin"
(NOON2004), Tokyo, Japan, February 11-15, 200
Compositeness Effects in the Anomalous Weak-Magnetic Moment of Leptons
We investigate the effects induced by excited leptons, at the one-loop level,
in the anomalous magnetic and weak-magnetic form factors of the leptons. Using
a general effective Lagrangian approach to describe the couplings of the
excited leptons, we compute their contributions to the weak-magnetic moment of
the lepton, which can be measured on the peak, and we compare it
with the contributions to , measured at low energies.Comment: Latex File using Rev Tex. 16 pages 5 .eps figure
Flavoured Soft Leptogenesis
We study the impact of flavour in ``soft leptogenesis'' (leptogenesis induced
by soft supersymmetry breaking terms). We address the question of how flavour
effects can affect the region of parameters in which successful soft
leptogenesis induced by CP violation in the right-handed sneutrino mixing is
possible. We find that for decays which occur in the intermediate to strong
washout regimes for all flavours, the produced total asymmetry can be up
to a factor larger than the one predicted with flavour effects
being neglected. This enhancement, permits slightly larger values of the
required lepton violating soft bilinear term.Comment: 20 pages, 5 figures. Version accepted in JHEP. Results unchange
Present Bounds on New Neutral Vector Resonances from Electroweak Gauge Boson Pair Production at the LHC
Several extensions of the Standard Model predict the existence of new neutral
spin-1 resonances associated to the electroweak symmetry breaking sector. Using
the data from ATLAS (with integrated luminosity of L=1.02 fb^{-1}) and CMS
(with integrated luminosity of L=1.55 fb^{-1}) on the production of W+W- pairs
through the process pp -> l^+ l^{\prime -} \sla{E}_T, we place model
independent bounds on these new vector resonances masses, couplings and widths.
Our analyses show that the present data excludes new neutral vector resonances
with masses up to 1-2.3 TeV depending on their couplings and widths. We also
demonstrate how to extend our analysis framework to different models working a
specific example.Comment: 10 pages, 6 figure
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