@misc{10481/104890,
year = {2025},
month = {4},
url = {https://hdl.handle.net/10481/104890},
abstract = {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 confguration 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-favour neutrino oscillation scenario, where
the third neutrino mass state ν3 decays into an invisible state, e.g. a sterile neutrino. The
resulting best ft of the invisible neutrino decay parameter is α3 = 0.92+1.08−0.57 × 10−4 eV2,
corresponding to a scenario with θ23 in the second octant and normal neutrino mass ordering.
The results are consistent with the Standard Model, within a 2.1 σ interval},
organization = {European Union — NextGenerationEU},
organization = {European Union’s Horizon 2020 Research and Innovation Programme (101142396)},
organization = {Ministerio de Ciencia, Innovación y Universidades (MCIN/AEI/10.13039/501100011033)},
organization = {European Union’s Horizon 2020 Research and Innovation Programme (101008324)},
publisher = {Springer},
keywords = {Beyond Standard Model},
keywords = {Neutrino Detectors and Telescopes (experiments),},
keywords = {Oscillation},
title = {Probing invisible neutrino decay with the frst six detection units of KM3NeT/ORCA},
doi = {10.1007/JHEP04(2025)105},
author = {Aiello, S. and The KM3NeT Collaboration, / and Díaz García, Antonio Francisco},
}