Abstract 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 $$\Delta m^2_{21}$$ Δ m 21 2 . In the ranges allowed by previous measurements, the best-fit $$\Delta m^2_{21}$$ Δ m 21 2 is ( $$8.85^{+1.10}_{-1.33}$$ 8 . 85 - 1.33 + 1.10 ) $$\times $$ × $$10^{-5}$$ 10 - 5 $$\hbox {eV}^2$$ eV 2 . This measurement is continuing in the next phases of SNO+ and is expected to surpass the present global precision on $$\Delta m^2_{21}$$ Δ m 21 2 with about three years of data.

The Lousal Mine (Iberian Pyrite Belt, Portugal) was operated from 1900 to 1988 for the extraction of massive sulphides and was later rehabilitated as a science museum. It was selected as a test site for underground muon tomography applied to geophysical surveys, as part of the LouMu project. This study focuses on seismic tomography to analyse the subsurface above the mine gallery, primarily surveyed by a muography telescope, which was developed specifically for this site by the Laboratory of Instrumentation and Experimental Particle Physics. To validate the muon tomography results, an initial approach using conventional 2D seismic refraction failed to reach the Waldemar gallery depth, due to limited seismic ray coverage. Therefore, an innovative setup using surface shots and in-gallery geophones was implemented, providing full ray coverage. A 3D velocity model was then produced using the ATOM3D code, which enabled the integration of this configuration and performed travel-time inversion for velocity calculation. A regional dextral strike-slip fault, the Corona Fault (CF), crosses the surveyed area, and served as the main focus of this investigation. The 3D velocity model successfully detected this structure, that corresponded to the boundary between positive anomalies of the Volcano-Sedimentary Complex (VSC) and negative anomalies of the Phyllite-Quartzite Group (PQG). The absolute velocity distribution showed a distinct offset around the Corona Fault (CF), indicating a dextral strike-slip mechanism. A subvertical extension of secondary faults was observed, reflecting deformation similar to that of the main tectonic context. Previous data from the gallery confirmed that these results are consistent with the known geology and can serve as a reference for the muon tomography interpretations.

The Pierre Auger Observatory is the world’s largest facility dedicated to studying ultra-high-energy cosmic rays (UHECRs). Located in Argentina, it spans 3,000 square kilometers and utilizes a hybrid detection system comprising over 1,600 Water-Cherenkov detectors and fluorescence telescopes. Since its inception in 2004, the Observatory has provided groundbreaking insights into the energy spectrum, mass composition, and arrival direction anisotropies of cosmic rays. Phase-I data analysis, covering the years 2004-2022, has revealed critical features such as large-scale anisotropies and spectral features such as the instep and the suppression of flux at the highest energies, thus advancing our understanding of the origin and propagation of UHECRs. The hybrid detection approach has enabled precise measurements of air showers and muon content, offering constraints on hadronic interaction models. Furthermore, searches for neutral particles have been performed, contributing to multi-messenger astrophysics. The ongoing AugerPrime upgrade aims to refine mass composition studies by integrating scintillator detectors, improved electronics, underground muon detectors, and radio antennas, enhancing sensitivity to primary cosmic-ray properties. We present the key scientific achievements from Phase I and discuss the transformative potential of AugerPrime in addressing fundamental questions about the origin of UHECRs.