Rafael Antunes Nóbrega
A5011636769- Particle Detector Development and Performance
- Particle physics theoretical and experimental studies
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Radiation Detection and Scintillator Technologies
- Astrophysics and Cosmic Phenomena
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- CCD and CMOS Imaging Sensors
- Superconducting Materials and Applications
- Atomic and Subatomic Physics Research
- Particle Accelerators and Free-Electron Lasers
- Advancements in PLL and VCO Technologies
- Railway Engineering and Dynamics
- Distributed and Parallel Computing Systems
- Analog and Mixed-Signal Circuit Design
- Non-Destructive Testing Techniques
- Computational Physics and Python Applications
- Nuclear Physics and Applications
- Welding Techniques and Residual Stresses
- Quantum-Dot Cellular Automata
- Data-Driven Disease Surveillance
- Neural Networks and Applications
- Atmospheric Ozone and Climate
- Radio Astronomy Observations and Technology
Universidade Federal de Juiz de Fora
2015-2024
Sapienza University of Rome
2006-2024
Istituto Nazionale di Fisica Nucleare
2006-2024
University of Coimbra
2024
Gran Sasso Science Institute
2024
Istituto Nazionale di Fisica Nucleare, Sezione di Roma Tre
2024
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso
2024
Roma Tre University
2024
Istituto Nazionale di Fisica Nucleare, Sezione di Roma I
2006-2022
University of Rome Tor Vergata
2010
The performance of the LHCb Muon system and its stability across full 2010 data taking with LHC running at ps = 7 TeV energy is studied. optimization detector setting time calibration performed first collisions delivered by described. Particle rates, measured for wide range luminosities beam operation conditions experienced during run, are compared values expected from simulation. space alignment detectors, chamber efficiency, resolution cluster size evaluated. found to be as specifications...
Decays of b hadrons into final states containing a D0 meson and muon are used to measure the anti-b production cross-section in proton-proton collisions at centre-of-mass energy 7 TeV LHC. In pseudorapidity interval 2 < eta 6 integrated over all transverse momenta we find that average produce b-flavoured or anti-b-flavoured is (75.3 +/- 5.4 13.0) microbarns.
The prospect of growth a railway system impacts both the network size and its occupation. Due to overloaded infrastructure, it is necessary increase reliability by adopting fast maintenance services reach economic security conditions. In this context, one major problem excessive friction caused wheels. This contingency may cause ruptures with severe consequences. While eddy's current approaches are adequate detect superficial damages in metal structures, there still open challenges...
The search for a novel technology able to detect and reconstruct nuclear electron recoil events with the energy of few keV has become more important now that large regions high-mass dark matter (DM) candidates have been excluded. Moreover, detector sensitive incoming particle direction will be crucial in case DM discovery open possibility studying its properties. Gaseous time projection chambers (TPC) optical readout are very promising detectors combining detailed event information provided...
Abstract Photobiomodulation (PBM) has been highlighted as a complementary therapeutic approach in dentistry, especially the postoperative management of dental extractions and associated complications such alveolar osteitis inferior nerve paresthesia. Using low-intensity lasers red infrared wavelengths, PBM promotes pain relief, reduction edema trismus, well accelerating tissue healing neural regeneration. The effectiveness varies according to protocol used, including place application,...
The production of K_short mesons in pp collisions at a centre-of-mass energy 0.9 TeV is studied with the LHCb detector Large Hadron Collider. luminosity analysed sample determined using novel technique, involving measurements beam currents, sizes and positions, found to be 6.8 +/- 1.0 microbarn^-1. differential prompt cross-section measured as function transverse momentum rapidity region 0 < pT 1.6 GeV/c 2.5 y 4.0. data are reasonable agreement previous generator expectations.
Using data collected with the LHCb detector in proton-proton collisions at a centre-of-mass energy of 7 TeV, semileptonic decays Bs -> Ds+ X mu nu and D0 K+ are detected. Two structures observed mass spectrum masses consistent known D^+_{s1}(2536) $D^{*+}_{s2}(2573) mesons. The measured branching fractions relative to total rate B(Bs D_{s2}^{*+} nu)/B(Bs nu)= (3.3\pm 1.0\pm 0.4)%, D_{s1}^+ munu)/B(Bs (5.4\pm 1.2\pm 0.5)%, where first uncertainty is statistical second systematic. This...
The CYGNO project has the goal to use a gaseous TPC with optical readout detect dark matter and solar neutrinos low energy threshold directionality. demonstrator will consist of 1 m 3 volume filled He:CF 4 gas mixture at atmospheric pressure. Optical high granularity CMOS sensors, combined fast light detectors, provide detailed reconstruction event topology. This allow discriminate nuclear recoil signal from background, mainly represented by electron recoils induced radioactivity. Thanks...
The search for a novel technology able to detect and reconstruct nuclear recoil events in the keV energy range has become more important as long vast regions of high mass WIMP-like Dark Matter candidate have been excluded. Gaseous Time Projection Chambers (TPC) with optical readout are very promising combining complete event information provided by TPC technique sensitivity granularity last generation scientific light sensors. A an amplification at anode obtained Gas Electron Multipliers...
We present the status of Angra Neutrino Experiment, aimed at developing an antineutrino detector for monitoring nuclear reactor activity. The comprises a 1.42 m3 Gadolinium-Water Cerenkov target, surrounded by 50 cm water shielding, placed inside commercial container about 30 m from core, II power plant, Brazil. 4 GW thermal will provide few thousand interactions per day. main challenge experiment is to overcome very high cosmic ray induced background sea level. text describes construction...
The Neutrinos Angra (ν-Angra) Experiment aims to construct an antineutrinos detection device capable of monitoring the dos Reis nuclear reactor activity. Nuclear reactors are intense sources antineutrinos, and thermal power released in fission process is directly related flow rate these particles. energy spectrum also provides valuable information on source isotopic composition. proposed detector will be equipped with photomultipliers tubes (PMT) which readout by a custom...
Abstract The nature of dark matter is still unknown and an experimental program to look for particles in our Galaxy should extend its sensitivity light the GeV mass range exploit directional information DM particle motion (Vahsen et al. CYGNUS: feasibility a nuclear recoil observatory with neutrinos, arXiv:2008.12587 , 2020). Cygno project studying gaseous time projection chamber operated at atmospheric pressure Gas Electron Multiplier (Sauli Nucl Instrum Meth A 386:531,...
The performance and long term stability of an optically readout Time Projection Chamber with electron amplification structure based on three Gas Electron Multipliers was studied. He/CF4 gas mixtures were used in two different proportions (60/40 70/30) a CYGNO prototype 7 litres sensitive volume. With electrical configurations providing very similar gains, almost full detection efficiency the whole detector volume found both mixtures, while light yield about 20% larger for 60/40 found....
The Neutrinos Angra Experiment has completed a major step by finishing the comissioning of detector and data acquisition system at experimental site located in dos Reis nuclear power plant. experiment consists water-based associated electronics, both designed with goal detecting electron antineutrinos produced reactor. detection is possible due to Inverse Beta Decay, where final products water are photons UV-to-visible range spectrum. assembled comprises three active volumes filled water:...
Railway track circuit failures can cause significant train delays and economic losses. A crucial point of the railway operation system is corrective maintenance process. During this operation, lines have circulation trains interrupted in respective sector, where traffic restoration occurs only after completing Depending on length circuit, identifying solving problem may take a long time. tool that assists fault detection during an inspection adds agility efficiency its cost reduction. This...
Time Projection Chambers (TPCs) working in combination with Gas Electron Multipliers (GEMs) produce a very sensitive detector capable of observing low energy events. This is achieved by capturing photons generated during the GEM electron multiplication process means high-resolution camera. The CYGNO experiment has recently developed TPC Triple coupled to noise and high spatial resolution CMOS sensor. For image analysis, an algorithm based on adapted version well-known DBSCAN was implemented,...
Abstract The CYGNO experiment aims to study rare events related the search for low-mass dark matter and solar neutrino events. One of main components background comes from cosmic rays that generate long tracks in detector’s images. interaction such particles with gas releases a variable energy profile along its trajectory form multiple cores can be easily reconstructed erroneously by being split into more than one cluster. Thus, this work offers newly adapted version well-known density-based...
The LHCb muon readout apparatus is made of 1368 Multi-Wire Proportional Chambers (MWPC) and 24 Gas Electron Multiplier (GEM) chambers connected to 7632 16-channel front-end boards, resulting in 122.112 channels be read out. After a pp collision, all the signals must within 25 ns, before next collision. large-scale system time constrains naturally led development custom complex control about 600 microcontrollers (μ <i xmlns:mml="http://www.w3.org/1998/Math/MathML"...
We have designed and implemented on a Xilinx SpartanIIE FPGA highly integrated time-multiplexing device by means of using multiple fixed delays. Signals coming from MWPCs (multi wire proportional chambers) front end readout circuitry can be multiplexed in time selected delay values. Up to 5 channels merged into one delays increments 150 ns. As consequence, usage multi-hit channel measure timing is possible. Inside the 36 8 multiplexing performed, resulting reduction, more than factor four,...