9,015 research outputs found
Enhancing with the -penguin
Lepton flavor violation (LFV) has been observed in neutrino oscillations. For
charged lepton FV decays only upper limits are known, but sizable branching
ratios are expected in many neutrino mass models. High scale models, such as
the classical supersymmetric seesaw, usually predict that decays are roughly a factor maller than the corresponding decays . Here we demonstrate that the -penguin diagram can give an
enhancement for decays in many extensions of the MSSM. We first
discuss why the -penguin is not dominant in the MSSM with seesaw and show
that much larger contributions from the -penguin are expected in general.
We then demonstrate the effect numerically in two example models, namely, the
supersymmetric inverse seesaw and R-parity violating supersymmetry.Comment: 5 pages; v2: minor corrections, final version to appear in PR
Predicting charged lepton flavor violation from 3-3-1 gauge symmetry
The simplest realization of the inverse seesaw mechanism in a gauge theory offers striking flavor
correlations between rare charged lepton flavor violating decays and the
measured neutrino oscillations parameters. The predictions follow from the
gauge structure itself without the need for any flavor symmetry. Such tight
complementarity between charged lepton flavor violation and oscillations
renders the scenario strictly testable.Comment: 7 pages, 2 figures; v2: discussion extended. Matches version
published in PR
Caracterización productiva y relación con el territorio de las explotaciones de ganado bovino. Estudio aplicado a la Reserva de la Biosfera de las sierras de Béjar y Francia
publishedTomo I . Sección: Sistemas Ganaderos-EconomÃa y Gestión. Sesión: Vacuno carne I. Ponencia nº
Neutrino Energy Reconstruction and the Shape of the CCQE-like Total Cross Section
We show that because of the multinucleon mechanism effects, the algorithm
used to reconstruct the neutrino energy is not adequate when dealing with
quasielastic-like events, and a distortion of the total flux unfolded cross
section shape is produced. This amounts to a redistribution of strength from
high to low energies, which gives rise to a sizable excess (deficit) of low
(high) energy neutrinos. This distortion of the shape leads to a good
description of the MiniBooNE unfolded CCQE-like cross sections published in
Phys.Rev. D81 (2010) 092005. However, these changes in the shape are artifacts
of the unfolding process that ignores multinucleon mechanisms.Comment: 11 pages, 6 figures. Some references and comments adde
Geometric structures on loop and path spaces
Is is known that the loop space associated to a Riemannian manifold admits a
quasi-symplectic structure. This article shows that this structure is not
likely to recover the underlying Riemannian metric by proving a result that is
a strong indication of the "almost" independence of the quasi-symplectic
structure with respect to the metric. Finally conditions to have contact
structures on these spaces are studied.Comment: Final version. To appear in Proceedings of Math. Sci. Indian Academy
of Science
Lepton flavor violation in low-scale seesaw models: SUSY and non-SUSY contributions
Taking the supersymmetric inverse seesaw mechanism as the explanation for
neutrino oscillation data, we investigate charged lepton flavor violation in
radiative and 3-body lepton decays as well as in neutrinoless
conversion in muonic atoms. In contrast to former studies, we take into account
all possible contributions: supersymmetric as well as non-supersymmetric. We
take CMSSM-like boundary conditions for the soft supersymmetry breaking
parameters. We find several regions where cancellations between various
contributions exist, reducing the lepton flavor violating rates by an order of
magnitude compared to the case where only the dominant contribution is taken
into account. This is in particular important for the correct interpretation of
existing data as well as for estimating the reach of near future experiments
where the sensitivity will be improved by one to two orders of magnitude.
Moreover, we demonstrate that ratios like BR()/BR() can be used to determine whether the supersymmetric contributions
dominate over the and contributions or vice versa.Comment: 75 pages, 7 figures. v3: references and comments added. Matches
published versio
- …