A5084779127- Atomic and Molecular Physics
- X-ray Spectroscopy and Fluorescence Analysis
- Advanced Chemical Physics Studies
- Electron and X-Ray Spectroscopy Techniques
- Nuclear Physics and Applications
- Mass Spectrometry Techniques and Applications
- Nuclear physics research studies
- Laser-induced spectroscopy and plasma
- Radiation Shielding Materials Analysis
- Cold Atom Physics and Bose-Einstein Condensates
- Radiation Detection and Scintillator Technologies
- X-ray Diffraction in Crystallography
- Heavy metals in environment
- Laser-Matter Interactions and Applications
- Advanced X-ray and CT Imaging
- Nuclear reactor physics and engineering
- Radioactivity and Radon Measurements
- Heavy Metal Exposure and Toxicity
- Radioactive Decay and Measurement Techniques
- Laser-Plasma Interactions and Diagnostics
- Heavy Metals in Plants
- Muon and positron interactions and applications
- Chemical Reactions and Mechanisms
- Particle accelerators and beam dynamics
- Trace Elements in Health
Universidade Nova de Lisboa
2016-2025
University of Lisbon
2006-2024
Universidade Federal de Sergipe
2024
Escola Superior de Saúde Egas Moniz
2021
LIP - Laboratory of Instrumentation and Experimental Particle Physics
2021
Institute of Science and Technology Austria
2018
Departamento de Ciência e Tecnologia
2009-2018
Rede de Química e Tecnologia
2017
Instituto Politécnico de Lisboa
2016
Fundação para a Ciência e Tecnologia
2014
Abstract The energy levels of hydrogen-like atomic systems can be calculated with great precision. Starting from their quantum mechanical solution, they have been refined over the years to include electron spin, relativistic and field effects, tiny shifts related complex structure nucleus. These caused by nuclear are vastly magnified in formed a negative muon nucleus, so spectroscopy these muonic ions used investigate high Here we present measurement two 2S–2P transitions helium-4 ion that...
Abstract Quantum electrodynamics (QED), the quantum field theory that describes interaction between light and matter, is commonly regarded as best-tested in modern physics. However, this claim mostly based on extremely precise studies performed domain of relatively low strengths atoms ions 1–6 . In realm very strong electromagnetic fields such heaviest highly charged (with nuclear charge Z ≫ 1), QED calculations enter a qualitatively different, non-perturbative regime. Yet, corresponding...
Despite their high relative abundance in our Universe, neutrinos are the least understood fundamental particles of nature. They also provide a unique system to study quantum coherence and wavelike nature systems due extremely weak interaction probabilities. In fact, properties emitted experimentally relevant sources virtually unknown spatial extent neutrino wavepacket is only loosely constrained by reactor oscillation data with spread 13 orders magnitude. Here, we present first direct limits...
Hydrogen-like light muonic ions, in which one negative muon replaces all of the electrons, are extremely sensitive probes nuclear structure. Using pulsed laser spectroscopy, we have measured three 2 S -2 P transitions helium-3 (μ 3 He + ) ion, an ion formed by a and bare nucleus. This allowed us to extract Lamb shift, fine structure splitting, -hyperfine splitting μ . Comparing these measurements with theory, determined root-mean-square charge radius helion ( nucleus) be r h = 1.97007(94)...
Formulas for the total ionization cross section by electron impact based on binary-encounter-dipole (BED) model and its simpler version, binary-encounter-Bethe (BEB) are extended to relativistic incident energies. Total sections hydrogen helium atoms from new formulas compared experimental data. Relativistic effects double of H He at energy $\ensuremath{\approx}300 \mathrm{keV}$ dominate thereafter. A simple modification original BED-BEB is proposed applications ion targets inner-shell...
The CREMA collaboration is pursuing a measurement of the ground-state hyperfine splitting (HFS) in muonic hydrogen ( \mu <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>μ</mml:mi></mml:math> p) with 1 ppm accuracy by means pulsed laser spectroscopy to determine two-photon-exchange contribution 2\times10^{-4}...
The relativistic version of the binary-encounter Bethe (BEB) model is used to calculate cross sections for K-shell ionization atoms by electron impact. BEB requires only two atomic constants, binding energy and kinetic K electrons. These constants are listed carbon antimony. Comparisons with available experimental data on N, O, Na, Al, Cl, Ca, Cu, Se Sb show good agreement. C, Mg, P, S, Cr, As Cd tabulated.
The 1s2s (3)S(1)→1s(2) (1)S(0) relativistic magnetic dipole transition in heliumlike argon, emitted by the plasma of an electron-cyclotron resonance ion source, has been measured using a double-flat crystal x-ray spectrometer. Such spectrometer, used for first time on highly charged transition, provides absolute (reference-free) measurements domain. We find energy 3104.1605(77) eV (2.5 ppm accuracy). This value is most accurate, reference-free measurement done such and good agreement with...
SUMMARY Selenium (Se) is an essential micronutrient for humans, yet its dietary intake low, mostly due to the low bioavailability in soils and therefore edible plant tissues. To overcome Se deficiency, breeding approach ( i.e ., genetic biofortification), namely rice, largely dependent on available pools. ensure success of biofortification with Se, agronomic can be accomplished through foliar application. Considering this background, main hypothesis work was centered application attain rice...
The Beryllium Electron capture in Superconducting Tunnel junctions (BeEST) experiment searches for evidence of heavy neutrino mass eigenstates the nuclear electron decay $^7$Be by precisely measuring recoil energy $^7$Li daughter. In Phase-III, BeEST has been scaled from a single superconducting tunnel junction (STJ) sensor to 36-pixel array increase sensitivity and mitigate gamma-induced backgrounds. Phase-III also uses new continuous data acquisition system that greatly increases...
O presente artigo busca compreender as consequências da utilização de telas na primeira infância para o processo aprendizagem leitura e escrita. Por meio uma revisão bibliográfica, objetiva-se entender como uso indiscriminado afeta processamento cognitivo desenvolvimento das funções executivas crianças, bem os impactos no alfabetização letramento confirmando efeitos negativos quanto ao inadequado tecnologias, mas orientando também a maneiras positivas desta ferramenta se utilizada...