Vincent Breton
A5007760591- Distributed and Parallel Computing Systems
- Scientific Computing and Data Management
- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- Medical Imaging Techniques and Applications
- High-Energy Particle Collisions Research
- Nuclear physics research studies
- Radiation Detection and Scintillator Technologies
- Radioactivity and Radon Measurements
- Parallel Computing and Optimization Techniques
- Genetics, Bioinformatics, and Biomedical Research
- Radioactive contamination and transfer
- Nuclear Physics and Applications
- Radiation Therapy and Dosimetry
- Atomic and Subatomic Physics Research
- Advanced X-ray and CT Imaging
- Advanced NMR Techniques and Applications
- Computational Drug Discovery Methods
- Bioinformatics and Genomic Networks
- Advanced Data Storage Technologies
- French Urban and Social Studies
- Genomics and Phylogenetic Studies
- Superconducting Materials and Applications
- COVID-19 epidemiological studies
- Diatoms and Algae Research
Université Clermont Auvergne
2016-2025
Centre National de la Recherche Scientifique
2016-2025
Institut National de Physique Nucléaire et de Physique des Particules
2011-2025
Clermont Université
2011-2024
Territoires
2019-2023
Laboratoire de Physique Corpusculaire
2011-2022
Ecosystem (Spain)
2007-2020
Université Grenoble Alpes
2017-2019
Institut dal Dicziunari Rumantsch Grischun
2018
Centre Jean Perrin
2011
Monte Carlo simulation is an essential tool in emission tomography that can assist the design of new medical imaging devices, optimization acquisition protocols and development or assessment image reconstruction algorithms correction techniques. GATE, Geant4 Application for Tomographic Emission, encapsulates libraries to achieve a modular, versatile, scripted toolkit adapted field nuclear medicine. In particular, GATE allows description time-dependent phenomena such as source detector...
The spin structure function of the neutron gn1 has been determined over range 0.03<x<0.6 at an average Q2 2 (GeV/c)2 by measuring asymmetry in deep inelastic scattering polarized electrons from a 3He target energies between 19 and 26 GeV. integral is found to be F10gn1(x)dx=-0.022±0.011. Earlier reported proton results together with Bjorken sum rule predict F10gn1(x)dx=-0.059±0.019.Received 1 April 1993DOI:https://doi.org/10.1103/PhysRevLett.71.959©1993 American Physical Society
Measurements are reported of the proton and deuteron spin structure functions ${g}_{1}^{p}$ ${g}_{1}^{d}$ at beam energies 29.1, 16.2, 9.7 GeV, ${g}_{2}^{p}$ ${g}_{2}^{d}$ a energy 29.1 GeV. The integrals ${\ensuremath{\Gamma}}_{p}={\ensuremath{\int}}_{0}^{1}{g}_{1}^{p}{(x,Q}^{2})dx$ ${\ensuremath{\Gamma}}_{d}={\ensuremath{\int}}_{0}^{1}{g}_{1}^{d}{(x,Q}^{2})dx$ were evaluated fixed ${Q}^{2}=3(\mathrm{GeV}{/c)}^{2}$ using full data set to yield...
We report on a precision measurement of the neutron spin structure function ${g}_{1}^{n}$ using deep inelastic scattering polarized electrons by ${}^{3}\mathrm{He}$. For kinematic range $0.014<x<0.7$ and $1<{Q}^{2}<17(\mathrm{GeV}/c{)}^{2}$, we obtain $\ensuremath{\int}{0.014}^{0.7}{g}_{1}^{n}(x)dx\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}0.036\ifmmode\pm\else\textpm\fi{}0.004(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.005(\mathrm{syst})$ at an average...
We have measured the ratio $\frac{{g}_{1}^{p}}{{F}_{1}^{p}}$ over range $0.029<x<0.8$ and $1.3<{Q}^{2}<10$ ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$ using deep-inelastic scattering of polarized electrons from ammonia. An evaluation integral $\ensuremath{\int}{0}^{1}{g}_{1}^{p}(x, {Q}^{2})\mathrm{dx}$ at fixed ${Q}^{2}=3$ yields 0.127\ifmmode\pm\else\textpm\fi{}0.004(stat)\ifmmode\pm\else\textpm\fi{}0.010(syst), in agreement with previous experiments, but well below Ellis-Jaffe sum...
The neutron longitudinal and transverse asymmetries A1n A2n have been extracted from deep inelastic scattering of polarized electrons by a He3 target at incident energies 19.42, 22.66, 25.51 GeV. measurement allows for the determination spin structure functions g1n(x, Q2) g2n(x, over range 0.03<x<0.6 an average Q2 2 (GeV/c)2. data are used evaluation Ellis-Jaffe Bjorken sum rules. function is small negative within our measurement, yielding integral ∫0.030.6g1n(x)dx=−0.028±0.006 (stat)±0.006...
Structural biology, homology modelling and rational drug design require accurate three-dimensional macromolecular coordinates. However, the coordinates in Protein Data Bank (PDB) have not all been obtained using latest experimental computational methods. In this study a method is presented for automated re-refinement of existing structure models PDB. A large-scale benchmark with 16 807 PDB entries showed that they can be improved terms fit to deposited X-ray data as well geometric quality....
We report on a high-statistics measurement of the deuteron spin structure function ${g}_{1}^{d}$ at beam energy 29 GeV in kinematic range $0.029<x<0.8$ and $1<{Q}^{2}<10$ (GeV $/c$${)}^{2}$. The integral ${\ensuremath{\gamma}}_{1}^{d}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{\int}{1}^{}{g}_{1}^{d}\mathrm{dx}$ evaluated fixed ${Q}^{2}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}3$ $/c$${)}^{2}$ gives...
GATE, the Geant4 application for tomographic emission, is a simulation platform developed PET and SPECT. It combines powerful core, toolkit, with newly software components dedicated to nuclear medicine. In particular, it models passing of time during real acquisitions, allowing handle dynamic systems such as decaying source distributions or moving detectors. We present several series results that illustrate possibilities this new platform. The sources illustrated on dual-isotope acquisition...
We have measured proton and deuteron virtual photon-nucleon asymmetries ${A}_{2}^{p}$ ${A}_{2}^{d}$ structure functions ${g}_{2}^{p}$ ${g}_{2}^{d}$ over the range $0.03<x<0.8$ $1.3<{Q}^{2}<10(\mathrm{GeV}/c{)}^{2}$ by inelastically scattering polarized electrons off ammonia targets. Results for ${A}_{2}$ are significantly smaller than positivity limit $\sqrt{R}$ both Within experimental precision ${g}_{2}$ data well described twist-2 contribution, ${g}_{2}^{\mathrm{WW}}$. Twist-3 matrix...
In single photon emission computed tomography (SPECT) with parallel hole collimation, image reconstruction is usually performed as a set of bidimensional (2D) analytical or iterative reconstructions. This approach ignores the tridimensional (3D) nature scatter and detector response function that affects detected signal. To deal 3D formation process, can be used by considering projector modelling spread photons. this paper, we investigate value using accurate Monte Carlo simulations to...
The GATE Monte Carlo simulation platform based on the GEANT4 toolkit has come into widespread use for simulating positron emission tomography (PET) and single photon computed (SPECT) imaging devices. Here, we explore its calculating electron dose distributions in water. Mono-energetic point kernels pencil beam water are calculated different energies between 15 keV 20 MeV by means of 6.0, which makes version 9.2 Standard Electromagnetic Physics Package. results compared to well-validated...
Biological experiments conducted in underground laboratories over the last decade have shown that life can respond to relatively small changes radiation background unconventional ways. Rapid cell growth, indicative of hormetic behaviour and long-term inheritable antioxidant regulation been observed response should be almost undetectable cells. Here, we summarize recent body date, outline potential mechanisms (such as signalling, DNA repair regulation) could mediate cells low backgrounds. We...