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Accurate measurement of the cosmogenic muon-induced neutron yield is crucial for constraining a significant background in a wide range of low-energy physics searches. Although previous underground experiments have measured this yield across various cosmogenic muon energies, SNO+ is uniquely positioned due to its exposure to one of the highest average cosmogenic muon energies at \\(364\\,\\text{GeV}\\). Using ultra-pure water, we have determined a neutron yield of \\(Y_{n}=(3.38^{+0.23}_{-0.30})\\times10^{-4}\\,\\text{cm}^{2}\\text{g}^{-1}\\mu^{-1}\\) at SNO+. Comparison with simulations demonstrates clear agreement with the FLUKA neutron production model, highlighting discrepancies with the widely used GEANT4 model. Furthermore, this measurement reveals a lower cosmogenic neutron yield than that observed by the SNO experiment, which used heavy water under identical muon flux conditions. This result provides new evidence that nuclear structure and target material composition significantly influence neutron production by cosmogenic muons, offering fresh insight with important implications for the design and background modelling of future underground experiments.

The SNO+ collaboration reports its second spectral analysis of reactor antineutrino oscillation using 286 tonne-years of new data. The measured energies of reactor antineutrino candidates were fitted to obtain the second-most precise determination of the neutrino mass-squared difference \\(\\Delta m^2_{21}\\) = (\\(7.96^{+0.48}_{-0.42}\\)) \\(\\times\\) 10\\(^{-5}\\) eV\\(^2\\). Constraining \\(\\Delta m^2_{21}\\) and \\(\\sin^2\\theta_{12}\\) with measurements from long-baseline reactor antineutrino and solar neutrino experiments yields \\(\\Delta m^2_{21}\\) = (\\(7.58^{+0.18}_{-0.17}\\)) \\(\\times\\) 10\\(^{-5}\\) eV\\(^2\\) and \\(\\sin^2\\theta_{12} = 0.308 \\pm 0.013\\). This fit also yields a first measurement of the flux of geoneutrinos in the Western Hemisphere, with \\(73^{+47}_{-43}\\) TNU at SNO+.

The SNO+ collaboration reports its first spectral analysis of long-baseline reactor antineutrino oscillation using 114 tonne-years of data. Fitting the neutrino oscillation probability to the observed energy spectrum yields constraints on the neutrino mass-squared difference \\( m^2_21\\). In the ranges allowed by previous measurements, the best-fit \\( m^2_21\\) is (8.85\\(^+1.10_-1.33\\)) \\(\\) 10\\(^-5\\) eV\\(^2\\). This measurement is continuing in the next phases of SNO+ and is expected to surpass the present global precision on \\( m^2_21\\) with about three years of data.

Accurate measurement of the cosmogenic muon-induced neutron yield is crucial for constraining a significant background in a wide range of low-energy physics searches. Although previous underground experiments have measured this yield across various cosmogenic muon energies, SNO+ is uniquely positioned due to its exposure to one of the highest average cosmogenic muon energies at \\(364\\,\\textup{GeV}\\). Using ultra-pure water, we have determined a neutron yield of \\(Y_{n}=(3.38^{+0.23}_{-0.30})\\times10^{-4}\\,\\textup{cm}^{2}\\textup{g}^{-1}\\mu^{-1}\\) at SNO+. Comparison with simulations demonstrates clear agreement with the \\textsc{FLUKA} neutron production model, highlighting discrepancies with the widely used \\textsc{GEANT4} model. Furthermore, this measurement reveals a lower cosmogenic neutron yield than that observed by the SNO experiment, which used heavy water under identical muon flux conditions. This result provides new evidence that nuclear structure and target material composition significantly influence neutron production by cosmogenic muons, offering fresh insight with important implications for the design and background modelling of future underground experiments.

The SNO+ Collaboration reports new results on reactor antineutrino oscillations using data acquired from May 2022 through July 2025. The spectral analysis of a flux dominated by nuclear reactors at 240, 350, and 355 kilometers yields the mass-squared difference \\(\\Delta m^2_{21}=(7.93^{+0.21}_{-0.24})\\times 10^{-5}\\) eV\\(^2\\). This result is compatible with and approaches the precision of the only other long-baseline reactor antineutrino measurement, by KamLAND. Combining these measurements, along with those from solar neutrino experiments, the global values of the neutrino mixing parameters become: \\(\\Delta m^2_{21}\\) = \\((7.63\\pm0.17)\\times 10^{-5}\\) eV\\(^2\\) and \\(\\sin^2{\\theta_{12}}=0.310\\pm0.012\\). The analysis of geoneutrinos at SNO+ is also improved, with a measured signal of 49\\(^{+13}_{-12}\\) TNU.

The SNO+ Collaboration reports the first evidence of \\(^{8}\\text{B}\\) solar neutrinos interacting on \\(^{13}\\text{C}\\) nuclei. The charged current interaction proceeds through \\(^{13}\\text{C} + \\nu_e \\rightarrow {}^{13}\\text{N} + e^-\\) which is followed, with a 10 minute half-life, by \\({}^{13}\\text{N} \\rightarrow {}^{13}\\text{C} + e^+ +\\nu_e .\\) The detection strategy is based on the delayed coincidence between the electron and the positron. Evidence for the charged current signal is presented with a significance of 4.2\\(\\sigma\\). Using the natural abundance of \\(^{13}\\text{C}\\) present in the scintillator, 5.7 tonnes of \\(^{13}\\text{C}\\) over 231 days of data were used in this analysis. The 5.6\\(^{+3.0}_{-2.3}\\) observed events in the data set are consistent with the expectation of 4.7\\(^{+0.6}_{-1.3}\\) events. This result is the second real-time measurement of CC interactions of \\(^{8}\\text{B}\\) neutrinos with nuclei and constitutes the lowest energy observation of neutrino interactions on \\(^{13}\\text{C}\\) generally. This enables the first direct measurement of the CC \\(\\nu_e\\) reaction to the ground state of \\({}^{13}\\text{N}\\), yielding an average cross section of \\((16.1 ^{+8.5}_{-6.7} (\\text{stat.}) ^{+1.6}_{-2.7} (\\text{syst.}) )\\times 10^{-43}\\) cm\\(^{2}\\) over the relevant \\(^{8}\\text{B}\\) solar neutrino energies.

The SNO+ detector operated initially as a water Cherenkov detector. The implementation of a sealed covergas system midway through water data taking resulted in a significant reduction in the activity of \\(^222\\)Rn daughters in the detector and allowed the lowest background to the solar electron scattering signal above 5 MeV achieved to date. This paper reports an updated SNO+ water phase \\(^8\\)B solar neutrino analysis with a total livetime of 282.4 days and an analysis threshold of 3.5 MeV. The \\(^8\\)B solar neutrino flux is found to be \\((2.32^+0.18_-0.17(stat.)^+0.07_-0.05(syst.))10^6\\) cm\\(^-2\\)s\\(^-1\\) assuming no neutrino oscillations, or \\((5.36^+0.41_-0.39(stat.)^+0.17_-0.16(syst.) )10^6\\) cm\\(^-2\\)s\\(^-1\\) assuming standard neutrino oscillation parameters, in good agreement with both previous measurements and Standard Solar Model Calculations. The electron recoil spectrum is presented above 3.5 MeV.

The enclosed data release consists of a subset of the calibration data from the Majorana Demonstrator experiment. Each Majorana event is accompanied by raw Germanium detector waveforms, pulse shape discrimination cuts, and calibrated final energies, all shared in an HDF5 file format along with relevant metadata. This release is specifically designed to support the training and testing of Artificial Intelligence (AI) and Machine Learning (ML) algorithms upon our data. This document is structured as follows. Section I provides an overview of the dataset's content and format; Section II outlines the location of this dataset and the method for accessing it; Section III presents the NPML Machine Learning Challenge associated with this dataset; Section IV contains a disclaimer from the Majorana collaboration regarding the use of this dataset; Appendix A contains technical details of this data release. Please direct questions about the material provided within this release to liaobo77@ucsd.edu (A. Li).