Probing invisible neutrino decay with the first six detection units of KM3NeT/ORCA

[EN] In the era of precision measurements of neutrino oscillation parameters, it is necessary for experiments to disentangle discrepancies that may indicate physics beyond the Standard Model in the neutrino sector. KM3NeT/ORCA is a water Cherenkov neutrino detector under construction and anchored at...

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Detalles Bibliográficos
Autores: Aiello, S., Albert, A., Alhebsi, A.R., Alshamsi, M., Alves Garre, S., Ambrosone, A., Ameli, F., Andre, M., Aphecetche, L., Aublin, J., Badaracco, F., Bailly-Salins, L., Bardacová, Z., Ardid, Miguel|||0000-0002-3199-594X, Ardid, S.|||0000-0003-4821-6655, García-Méndez, Juan|||0000-0002-1580-0647, C.A.~Quiroz-Rangel|||0009-0002-3446-8747
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/221167
Acceso en línea:https://riunet.upv.es/handle/10251/221167
Access Level:acceso abierto
Palabra clave:Beyond Standard Model
Neutrino Detectors and Telescopes (experiments)
Oscillation
Descripción
Sumario:[EN] In the era of precision measurements of neutrino oscillation parameters, it is necessary for experiments to disentangle discrepancies that may indicate physics beyond the Standard Model in the neutrino sector. KM3NeT/ORCA is a water Cherenkov neutrino detector under construction and anchored at the bottom of the Mediterranean Sea. The detector is designed to study the oscillations of atmospheric neutrinos and determine the neutrino mass ordering. This paper focuses on the initial configuration of ORCA, referred to as ORCA6, which comprises six out of the foreseen 115 detection units of photosensors. A high-purity neutrino sample was extracted during 2020 and 2021, corresponding to an exposure of 433 kton-years. This sample is analysed following a binned log-likelihood approach to search for invisible neutrino decay, in a three-flavour neutrino oscillation scenario, where the third neutrino mass state nu 3 decays into an invisible state, e.g. a sterile neutrino. The resulting best fit of the invisible neutrino decay parameter is alpha 3=0.92-0.57+1.08x10-4\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\alpha}_3={0.92}_{-0.57}<^>{+1.08}\times {10}<^>{-4} $$\end{document} eV2, corresponding to a scenario with theta 23 in the second octant and normal neutrino mass ordering. The results are consistent with the Standard Model, within a 2.1 sigma interval.