Neutrino mass ordering determination through combined analysis with JUNO and KM3NeT/ORCA

• Published in: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
• Main Authors: Athayde Marcondes de André, João Pedro, Chau, Nhan, Dracos, Marcos, Kalousis, Leonidas N, Kouchner, Antoine, Van Elewyck, Véronique
• Other Authors: Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), KM3NeT, JUNO
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2023
• Subjects: neutrino; atmosphere; oscillation; JUNO; sensitivity; KM3NeT; tension; GeV; nuclear reactor; electron; ORCA; Neutrino mass ordering; mass; antineutrino; spectrum; interference; effect; matter; [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det]; Orca
• Online Access: https://hal.science/hal-04157443; https://hal.science/hal-04157443/document; https://hal.science/hal-04157443/file/proceedings_JUNO_ORCA_RICH2022.pdf; https://doi.org/10.1016/j.nima.2023.168438

International audience The determination of neutrino mass ordering (NMO) is one of the prime goals of several neutrino experiments. KM3NeT/ORCA and JUNO are two next-generation neutrino oscillation experiments both aiming at addressing this question. ORCA can determine the NMO by probing Earth matter effects on the oscillation of atmospheric neutrinos in the GeV energy range. JUNO, on the other hand, is sensitive to the NMO by investigating the interference effects of fast oscillations in the reactor electron antineutrino spectrum at medium baseline. This contribution presents the potential of determining the NMO through a combined analysis of JUNO and ORCA data. When measuring the Δ m 31 2 with a wrong ordering assumption, the best-fit values are different between the two experiments. This tension, together with good constraints on the Δ m 31 2 measurement by both experiments, enhances the combined NMO sensitivity beyond the simple sum of their sensitivities. The analysis shows that a 5 σ significance is reachable in less than 2 years of data taking with both experiments for true normal neutrino mass ordering, assuming current global best-fit values of the oscillation parameters, while 6 years will be needed for any other parameter set.