Evidence for Normal Neutrino Ordering with Combined Atmospheric Neutrino Experiments
Abstract
We present a combined analysis of the latest publicly available atmospheric neutrino data from Super-Kamiokande including all data-taking stages previous to the gadolinium phase, IceCube-DeepCore, and the six-detection-unit configuration of KM3NeT/ORCA. Our fit uses all event samples simultaneously and treats the systematic uncertainties shared among experiments as fully correlated, while detector-response uncertainties are modeled independently for each experiment. The combined data constrain the atmospheric oscillation parameters to Δm231 = 2.44+0.06−0.04 × 10−3 eV2 and sin2θ23 = 0.52+0.03−0.04, with a precision of 2.2% and 6.1%, respectively, which is competitive with current accelerator-based measurements, and independently constrain the CP-violating phase to δCP = 1.30+0.24−0.28 π. Finally, comparing the orderings of the neutrino mass spectrum, we find a preference for the normal ordering with Δχ2 = 11.0; further calibrated with pseudoexperiments, we exclude the inverted ordering at 99.95% confidence level (3.3σ). In a joint fit including 207 days of JUNO data, we further exclude the inverted ordering at Δχ2 = 15.1, corresponding to $3.9 σ$.
Related
- Flavor Tomography of Long-Lived Neutrino-Mass Mediators: Probing the Neutrino Mass Ordering at the HL-LHC
- Atmospheric Neutrino Oscillations: the Full Picture
- Measurement of Neutrino Oscillation Parameters at JUNO and Indication of the Neutrino Mass Ordering
- Neutrino texture-zeros after JUNO’s first results: implications for long-baseline neutrino experiments
- Benchmarking Nucleon Production in Hadron Interactions Relevant for GeV-scale Neutrino Experiments
BibTeX
@misc{jin2026evidence,
title = {{Evidence for Normal Neutrino Ordering with Combined Atmospheric Neutrino Experiments}},
author = {Miaochen Jin and Carlos A. Argüelles and Pablo Fernández-Menéndez and Iván Martínez-Soler},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.12208},
eprint = {2610.12208},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.12208},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Evidence for Normal Neutrino Ordering with Combined Atmospheric Neutrino Experiments
AU - Miaochen Jin
AU - Carlos A. Argüelles
AU - Pablo Fernández-Menéndez
AU - Iván Martínez-Soler
PY - 2026
DA - 2026/10/21
PB - arXiv
DO - 10.48550/arxiv.2610.12208
UR - https://arxiv.org/abs/2610.12208
AB - We present a combined analysis of the latest publicly available atmospheric neutrino data from Super-Kamiokande including all data-taking stages previous to the gadolinium phase, IceCube-DeepCore, and the six-detection-unit configuration of KM3NeT/ORCA. Our fit uses all event samples simultaneously and treats the systematic uncertainties shared among experiments as fully correlated, while detector-response uncertainties are modeled independently for each experiment. The combined data constrain the atmospheric oscillation parameters to Δm^2_31 = 2.44^+0.06_−0.04 × 10^−3 eV^2 and sin^2θ_23 = 0.52^+0.03_−0.04, with a precision of 2.2% and 6.1%, respectively, which is competitive with current accelerator-based measurements, and independently constrain the CP-violating phase to δ_CP = 1.30^+0.24_−0.28 π. Finally, comparing the orderings of the neutrino mass spectrum, we find a preference for the normal ordering with Δχ^2 = 11.0; further calibrated with pseudoexperiments, we exclude the inverted ordering at 99.95% confidence level (3.3σ). In a joint fit including 207 days of JUNO data, we further exclude the inverted ordering at Δχ^2 = 15.1, corresponding to $3.9 σ$.
ER -