arXiv subjects

T. S. Bezerra

Publications and source records attributed to T. S. Bezerra.

5 recordsLinked to original sources

arXiv2025

Measurement of reactor antineutrino oscillation at SNO+

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 $Δm^2_{21}$ = ($7.96^{+0.48}_{-0.42}$) $\times$ 10$^{-5}$ eV$^2$. Constraining $Δm^2_{21}$ and $\sin^2θ_{12}$ with measurements from long-baseline reactor antineutrino and solar neutrino experiments yields $Δm^2_{21}$ = ($7.58^{+0.18}_{-0.17}$) $\times$ 10$^{-5}$ eV$^2$ and $\sin^2θ_{12} = 0.308 \pm 0.013$. This fit also yields a first measurement of the flux of geoneutrinos in the Western Hemisphere, with $73^{+47}_{-43}$ TNU at SNO+.

hep-ex↗

arXiv2025

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

hep-ex↗

arXiv2024

Event-by-Event Direction Reconstruction of Solar Neutrinos in a High Light-Yield Liquid Scintillator

The direction of individual $^8$B solar neutrinos has been reconstructed using the SNO+ liquid scintillator detector. Prompt, directional Cherenkov light was separated from the slower, isotropic scintillation light using time information, and a maximum likelihood method was used to reconstruct the direction of individual scattered electrons. A clear directional signal was observed, correlated with the solar angle. The observation was aided by a period of low primary fluor concentration that resulted in a slower scintillator decay time. This is the first time that event-by-event direction reconstruction in high light-yield liquid scintillator has been demonstrated in a large-scale detector.

hep-ex↗

arXiv2023

Evidence of Antineutrinos from Distant Reactors using Pure Water at SNO+

The SNO+ Collaboration reports the first evidence of reactor antineutrinos in a Cherenkov detector. The nearest nuclear reactors are located 240~km away in Ontario, Canada. This analysis uses events with energies lower than in any previous analysis with a large water Cherenkov detector. Two analytical methods are used to distinguish reactor antineutrinos from background events in 190 days of data and yield consistent evidence for antineutrinos with a combined significance of 3.5$σ$.

nucl-ex↗

arXiv2022

Improved search for invisible modes of nucleon decay in water with the SNO+ detector

This paper reports results from a search for single and multi-nucleon disappearance from the $^{16}$O nucleus in water within the \snoplus{} detector using all of the available data. These so-called "invisible" decays do not directly deposit energy within the detector but are instead detected through their subsequent nuclear de-excitation and gamma-ray emission. New limits are given for the partial lifetimes: $τ(n\rightarrow inv) > 9.0\times10^{29}$ years, $τ(p\rightarrow inv) > 9.6\times10^{29}$ years, $τ(nn\rightarrow inv) > 1.5\times10^{28}$ years, $τ(np\rightarrow inv) > 6.0\times10^{28}$ years, and $τ(pp\rightarrow inv) > 1.1\times10^{29}$ years at 90\% Bayesian credibility level (with a prior uniform in rate). All but the ($nn\rightarrow inv$) results improve on existing limits by a factor of about 3.

hep-ex↗