arXiv subjects

João A. B. Coelho

Publications and source records attributed to João A. B. Coelho.

5 recordsLinked to original sources

arXiv2026

Sensitivity of neutrino oscillations to the Earth's interior properties

Understanding the Earth s internal structure remains a major challenge, as traditional geophysical methods face ambiguities in linking seismic observations to temperature, composition, or mass density variations. Atmospheric neutrinos offer a complementary probe: while traversing the Earth, they undergo flavor oscillations that depend on the local electron density, which reflects both mass density and composition.

physics.geo-ph↗

arXiv2024

Scalable DAQ system operating the CHIPS-5 neutrino detector

The CHIPS R&D project focuses on development of low-cost water Cherenkov neutrino detectors through novel design strategies and resourceful engineering. This work presents an end-to-end DAQ solution intended for a recent 5 kt CHIPS prototype, which is largely based on affordable mass-produced components. Much like the detector itself, the presented instrumentation is composed of modular arrays that can be scaled up and easily serviced. A single such array can carry up to 30 photomultiplier tubes (PMTs) accompanied by electronics that generate high voltage in-situ and deliver time resolution of up to 0.69 ns. In addition, the technology is compatible with the White Rabbit timing system, which can synchronize its elements to within 100 ps. While deployment issues did not permit the presented DAQ system to operate beyond initial evaluation, the presented hardware and software successfully passed numerous commissioning tests that demonstrated their viability for use in a large-scale neutrino detector, instrumented with thousands of PMTs.

physics.ins-det↗

arXiv2022

Snowmass Neutrino Frontier: NF01 Topical Group Report on Three-Flavor Neutrino Oscillations

This is the report from the Snowmass NF01 topical group and colleagues on the current status and expected future progress to understand the three-flavor neutrino oscillation picture.

hep-ph↗

arXiv2017

Decoherence, matter effect, neutrino hierarchy signature in long baseline experiments

Environmental decoherence of oscillating neutrinos of strength $Γ= (2.3 \pm 1.1) \times 10^{-23}$ GeV can explain how maximal $θ_{23}$ mixing observed at 295 km by T2K appears to be non-maximal at longer baselines. As shown recently by R. Oliveira, the MSW matter effect for neutrinos is altered by decoherence: In normal (inverted) mass hierarchy, a resonant enhancement of $ν_μ (\barν_μ) \rightarrow ν_{e} (\barν_{e})$ occurs for $6 < E_ν < 20$ GeV. Thus decoherence at the rated strength may be detectable as an excess of charged-current $ν_{e}$ events in the full $ν_μ$ exposures of MINOS+ and OPERA.

hep-ph↗

arXiv2017

Neutrino oscillation tomography of the Earth with KM3NeT-ORCA

KM3NeT-ORCA is a water-Cherenkov neutrino detector designed for studying the oscillations of atmospheric neutrinos, with the primary objective of measuring the neutrino mass ordering. Atmospheric neutrinos crossing the Earth undergo matter effects, modifying the pattern of their flavour oscillations. The study of the angular and energy distribution of neutrino events in ORCA can therefore provide tomographic information on the Earth's interior with an independent technique, complementary to the standard geophysics methods. Preliminary estimations based on a full Monte Carlo simulation of the detector response show that after ten years of operation the electron density can be measured with a precision of 3-5% in the mantle and 7-10% in the outer core - depending on the mass ordering.

physics.ins-det↗