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Limits on neutrino mixing with new heavy particles

We study the effects induced by new neutral fermions below their mass threshold, due to their possible mixing with the standard neutrinos. We use as experimental constraints the recent results on lepton universality, together with the measurement of the $\mu$ decay rate and the updated LEP data. In...

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Detalles Bibliográficos
Autores principales: Nardi, Enrico, Roulet, Esteban, Tommasini, Daniele
Lenguaje:eng
Publicado: 1994
Materias:
Acceso en línea:https://dx.doi.org/10.1016/0370-2693(94)90736-6
http://cds.cern.ch/record/676517
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author Nardi, Enrico
Roulet, Esteban
Tommasini, Daniele
author_facet Nardi, Enrico
Roulet, Esteban
Tommasini, Daniele
author_sort Nardi, Enrico
collection CERN
description We study the effects induced by new neutral fermions below their mass threshold, due to their possible mixing with the standard neutrinos. We use as experimental constraints the recent results on lepton universality, together with the measurement of the $\mu$ decay rate and the updated LEP data. In particular, the inclusion in our data set of the most recent determinations of the $\tau$ branching fractions, mass and lifetime implies that a previous indication of a non-vanishing mixing for $\nu_\tau$ is no longer present. We obtain new stringent limits on the mixing parameters between $\nu_e$, $\nu_\mu$, $\nu_\tau$ and heavy neutral states of different weak isospin. If no assumption on the type of neutrinos involved in the mixing is made, we find $\snue^2<0.0071$, $\snumu^2<0.0014$ and $\snutau^2<0.033$.
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institution Organización Europea para la Investigación Nuclear
language eng
publishDate 1994
record_format invenio
spelling cern-6765172019-09-30T06:29:59Zdoi:10.1016/0370-2693(94)90736-6http://cds.cern.ch/record/676517engNardi, EnricoRoulet, EstebanTommasini, DanieleLimits on neutrino mixing with new heavy particlesParticle Physics - PhenomenologyWe study the effects induced by new neutral fermions below their mass threshold, due to their possible mixing with the standard neutrinos. We use as experimental constraints the recent results on lepton universality, together with the measurement of the $\mu$ decay rate and the updated LEP data. In particular, the inclusion in our data set of the most recent determinations of the $\tau$ branching fractions, mass and lifetime implies that a previous indication of a non-vanishing mixing for $\nu_\tau$ is no longer present. We obtain new stringent limits on the mixing parameters between $\nu_e$, $\nu_\mu$, $\nu_\tau$ and heavy neutral states of different weak isospin. If no assumption on the type of neutrinos involved in the mixing is made, we find $\snue^2<0.0071$, $\snumu^2<0.0014$ and $\snutau^2<0.033$.hep-ph/9402224FTUV-93-47UM-TH-93-28CERN-TH-7150-94CERN-TH-7150-94FTUV-93-47UM-TH-93-28oai:cds.cern.ch:6765171994
spellingShingle Particle Physics - Phenomenology
Nardi, Enrico
Roulet, Esteban
Tommasini, Daniele
Limits on neutrino mixing with new heavy particles
title Limits on neutrino mixing with new heavy particles
title_full Limits on neutrino mixing with new heavy particles
title_fullStr Limits on neutrino mixing with new heavy particles
title_full_unstemmed Limits on neutrino mixing with new heavy particles
title_short Limits on neutrino mixing with new heavy particles
title_sort limits on neutrino mixing with new heavy particles
topic Particle Physics - Phenomenology
url https://dx.doi.org/10.1016/0370-2693(94)90736-6
http://cds.cern.ch/record/676517
work_keys_str_mv AT nardienrico limitsonneutrinomixingwithnewheavyparticles
AT rouletesteban limitsonneutrinomixingwithnewheavyparticles
AT tommasinidaniele limitsonneutrinomixingwithnewheavyparticles