H. Natal da Luz
A5107307314- High-Energy Particle Collisions Research
- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Radiation Detection and Scintillator Technologies
- Dark Matter and Cosmic Phenomena
- Nuclear Physics and Applications
- Atomic and Subatomic Physics Research
- Neutrino Physics Research
- Photocathodes and Microchannel Plates
- Nuclear reactor physics and engineering
- CCD and CMOS Imaging Sensors
- Muon and positron interactions and applications
- Electron and X-Ray Spectroscopy Techniques
- Cosmology and Gravitation Theories
- Plasma Diagnostics and Applications
- Nuclear physics research studies
- Air Quality Monitoring and Forecasting
- X-ray Spectroscopy and Fluorescence Analysis
- Statistical Methods and Bayesian Inference
- Pulsars and Gravitational Waves Research
- Advanced X-ray and CT Imaging
- Radiation Therapy and Dosimetry
- Non-Destructive Testing Techniques
- Electrostatic Discharge in Electronics
Hospital Universitário da Universidade de São Paulo
2016-2024
Czech Technical University in Prague
2021-2024
Universidade de São Paulo
2016-2022
A. Alikhanyan National Laboratory
2015-2020
Central China Normal University
2019-2020
Korea Institute of Science & Technology Information
2015-2019
Universidade Cidade de São Paulo
2018-2019
University of Houston
2018
University of Coimbra
2007-2016
University of Aveiro
2005-2011
Abstract The workshop “Shedding light on X17” brings together scientists looking for the existence of a possible new particle, often referred to as X17. This hypothetical particle can explain resonant structure observed at $$\sim $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>∼</mml:mo> </mml:math> 17 MeV in invariant mass electron-positron pairs, produced after excitation nuclei such $$^8\hbox {Be}$$ <mml:mrow> <mml:msup> <mml:mrow /> <mml:mn>8</mml:mn> </mml:msup>...
In this Technical Design Report (TDR) we describe the NEXT-100 detector that will search for neutrinoless double beta decay (ββ0ν) in 136XE at Laboratorio Subterráneo de Canfranc (LSC), Spain. The document formalizes design presented our Conceptual (CDR): an electroluminescence time projection chamber, with separate readout planes calorimetry and tracking, located, respectively, behind cathode anode. is designed to hold a maximum of about 150 kg xenon 15 bar, or 100 10 bar. This option...
NEXT is an experiment dedicated to neutrinoless double beta decay searches in xenon. The detector a TPC, holding 100 kg of high-pressure xenon enriched the 136 Xe isotope. It under construction Laboratorio Subterráneo de Canfranc Spain, and it will begin operations 2015. concept provides energy resolutionbetter than 1% FWHM topological signal that can be used reduce background. Furthermore, technology extrapolated 1 ton-scale experiment.
NEXT-DEMO is a high-pressure xenon gas TPC which acts as technological test-bed and demonstrator for the NEXT-100 neutrinoless double beta decay experiment. In its current configuration apparatus fully implements design concept. This an asymmetric TPC, with energy plane made of photomultipliers tracking silicon (SiPM) coated TPB. The detector in this new has been used to reconstruct characteristic signature electrons dense gas, demonstrating ability identify MIP ``blob'' regions. Moreover,...
We propose an EASY (Electroluminescent ApparatuS of high Yield) and SOFT (Separated Optimized FuncTion) time-projection chamber for the NEXT experiment, that will search neutrinoless double beta decay (bb0nu) in Xe-136. Our experiment must be competitive with new generation bb0nu searches already operation or construction. This requires a detector very good energy resolution (<1%), low background con- tamination (1E-4 counts/(keV \bullet kg y)) large target mass. In addition, it needs to...
NEXT-DEMO is a large-scale prototype of the NEXT-100 detector, an electroluminescent time projection chamber that will search for neutrinoless double beta decay \XE using 100–150 kg enriched xenon gas. was built to prove expected performance NEXT-100, namely, energy resolution better than 1% FWHM at 2.5 MeV and event topological reconstruction. In this paper we describe its initial results. A 1.75% 511 keV (which extrapolates 0.8% MeV) obtained 10 bar pressure gamma-ray calibration source....
The Neutrino Experiment with a Xenon TPC (NEXT) is intended to investigate the neutrinoless double beta decay of 136Xe, which requires severe suppression potential backgrounds. An extensive screening and material selection process underway for NEXT since control radiopurity levels materials be used in experimental set-up must rare event searches. First measurements based on Glow Discharge Mass Spectrometry gamma-ray spectroscopy using ultra-low background germanium detectors at Laboratorio...
We report on the results of an extensive R&D program aimed at evaluation Thick-Gas Electron Multipliers (THGEM) as potential active elements for Digital Hadron Calorimetry (DHCAL). Results are presented efficiency, pad multiplicity and discharge probability a 10x10 cm2 prototype detector with 1 readout pads. The is comprised single- or double-THGEM multipliers coupled to electrode either directly via resistive anode. Investigations employing standard discrete electronics KPiX system have...
Abstract Spurious signals caused by microdischarges are a known effect inherent to all gaseous detectors. During the reconstruction in imaging and tracking detectors, such as time projection chambers, these added actual track-generated signal extra pixels or clusters, compromising performance of detector. The usual approach remove noise patterns is hardware-dependent heuristics conditions. In this work, we study usage denoising convolutional neural networks (NN) clean from Time Projection...
The operational characteristics of a Micromegas operating in pure xenon at the pressure range 1 to 10 bar are investigated. maximum charge gain achieved each is approximately constant, around 4x10^2, for pressures up 5 and decreasing slowly above this down values somewhat 10^2 bar. MM presents highest gains 4 bar, when compared other micropattern gaseous multipliers. lowest energy resolution obtained X-rays 22.1 keV exhibits steady increase with pressure, from 12% 1bar about 32% effective...
NEXT-MM is a general-purpose high pressure (10 bar, $\sim25$ l active volume) Xenon-based TPC, read out in charge mode with an 8 cm $\times$8 cm-segmented 700 cm$^2$ plane (1152 ch) of the latest microbulk-Micromegas technology. It has been recently commissioned at University Zaragoza as part R&D NEXT $0\nu\beta\beta$ experiment, although experiment's first stage currently being built based on SiPM/PMT-readout concept relying electroluminescence. Around 2 million events were collected during...
High-pressure xenon gas is an attractive detection medium for a variety of applications in fundamental and applied physics. In this paper we study the ionization scintillation properties at 10 bar pressure. For purpose, use source alpha particles NEXT-DEMO time projection chamber, large scale prototype NEXT-100 neutrinoless double beta decay experiment, three different drift electric field configurations. We measure electron velocity longitudinal diffusion, compare our results to...
ZiPD (zinc phosphodiesterase; synonyms are ElaC, ecoZ, RNaseZ and 3' tRNase) the iron-dependent redox enzyme FlRd (flavorubredoxin) from Escherichia coli represent prototypical cases of proteins sharing metallo-beta-lactamase fold that require strict metal selectivity for catalytic activity, yet their has only been partially understood. In contrast with hydrolytic proteins, FlRd-like enzymes have an atypical glutamate ligand, which replaces one otherwise conserved histidine ligand. X-ray...
<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> A Xe-based single photon counting x-ray imaging system, based on a Micro-Hole & Strip Plate (MHSP), using resistive charge division method was implemented. The MHSP is hybrid microstructure that combines in element the features of Gas Electron Multiplier (GEM) and Micro-strip Chamber (MSGC), presenting two multiplication stages. For 2D-imaging, GEM-like side (top side) structured with strips...
Silicon photomultipliers (SiPM) are the photon detectors chosen for tracking readout in NEXT, a neutrinoless \bb decay experiment which uses high pressure gaseous xenon time projection chamber (TPC). The reconstruction of event track and topology this detector is key handle background rejection. Among commercially available sensors that can be used tracking, SiPMs offer important advantages, mainly gain, ruggedness, cost-effectiveness radio-purity. Their main drawback, however, their non...
Beam studies of thin single- and double-stage THGEM-based detectors are presented. Several 10 × cm2configurations with a total thickness 5–6 mm (excluding readout electronics), 1 cm2 pads inductively coupled through resistive layer to APV-SRS electronics, were investigated muons pions. Detection efficiencies in the 98% range recorded an average pad-multiplicity ∼ 1.1. The anode resulted efficient discharge damping, few-volt potential drops; probabilities 10−7 for 10−6 pions configuration, at...
A technical description of NEXT-MM and its commissioning first performance is reported. Having an active volume ∼ 35 cm drift × 28 diameter, it constitutes the largest Micromegas-read TPC operated in Xenon ever constructed, made by a sectorial arrangement 4 single wafers manufactured with Microbulk technique to date. It equipped suitably pixelized readout sufficiently large sensitive ( 23 l) so as contain long 20 cm) electron tracks. First results obtained at 1 bar for Trymethylamine...
NEXT-100 experiment aims at searching the neutrinoless double-beta decay of 136Xe isotope using a TPC filled with 100 kg high-pressure gaseous xenon, 90% isotopic enrichment. The will take place Laboratorio Subterr'aneo de Canfranc (LSC), Spain. uses electroluminescence (EL) technology for energy measurement resolution better than 1% FWHM. xenon in additionally allows tracks two beta particles to be recorded, which are expected have length up 30 cm 10 bar pressure. ability record topological...
We present the results of first in-beam studies a medium size (10$\times$10 cm$^2$) Resistive-Plate WELL (RPWELL): single-sided THGEM coupled to pad anode through resistive layer high bulk resistivity ($\sim$10$^9 \Omega$cm). The 6.2~mm thick (excluding readout electronics) single-stage detector was studied with 150~GeV muons and pions. Signals were recorded from 1$\times$1 cm$^2$ square copper pads APV25-SRS electronics. single-element operated in Ne\(5% $\mathrm{CH_{4}}$) at gas gain few...