A5000565987- Magnetic confinement fusion research
- Laser-Plasma Interactions and Diagnostics
- Ionosphere and magnetosphere dynamics
- Geomagnetism and Paleomagnetism Studies
- Laser-induced spectroscopy and plasma
- High-pressure geophysics and materials
- Laser-Matter Interactions and Applications
- Gyrotron and Vacuum Electronics Research
- Solar and Space Plasma Dynamics
- Particle accelerators and beam dynamics
- Plasma Diagnostics and Applications
- Pulsed Power Technology Applications
- Laser Design and Applications
- Microwave Engineering and Waveguides
- Mechanical and Optical Resonators
- Dust and Plasma Wave Phenomena
- Ion-surface interactions and analysis
- Advanced Optical Sensing Technologies
- Ocular and Laser Science Research
- Nuclear Physics and Applications
- Terahertz technology and applications
- Scientific Research and Discoveries
- Particle Accelerators and Free-Electron Lasers
- Astro and Planetary Science
- Quantum chaos and dynamical systems
Laboratoire de Physique de l'ENS de Lyon
2018-2023
École Normale Supérieure de Lyon
2017-2023
Aix-Marseille Université
2013-2022
Physique des interactions ioniques et moléculaires
2019-2022
Centre National de la Recherche Scientifique
2013-2021
Université Claude Bernard Lyon 1
2017-2020
Centre Lasers Intenses et Applications
2014-2020
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2014-2020
Université de Bordeaux
2014-2020
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati
2020
Quasi-static magnetic-fields up to 800 T are generated in the interaction of intense laser pulses (500 J, 1 ns, ) with capacitor-coil targets different materials. The reproducible magnetic-field peak and rise-time, consistent pulse duration, were accurately inferred from measurements GHz-bandwidth inductor pickup coils (B-dot probes). Results Faraday rotation polarized optical light deflectometry energetic proton beams B-dot probe at early stages target charging, then disturbed by radiation...
Interaction of high-intensity laser pulses with solid targets results in generation large quantities energetic electrons that are the origin various effects such as intense x-ray emission, ion acceleration, and so on. Some these escaping target, leaving behind a significant positive electric charge creating strong electromagnetic pulse long after end pulse. We propose here detailed model target polarization induced by short an electron bunch. A specially designed experiment provides direct...
In this paper we describe the physical processes that lead to generation of giant electromagnetic pulses (GEMPs) at powerful laser facilities. Our study is based on experimental measurements both charging a solid target irradiated by an ultra-short, ultra-intense and detection emission in GHz domain. An unambiguous correlation between neutralization current holder shows source GEMP remaining positive charge inside after escape fast electrons accelerated laser. A simple model for calculating...
This paper provides an up-to-date review of the problems related to generation, detection and mitigation strong electromagnetic pulses created in interaction high-power, high-energy laser with different types solid targets. It includes new experimental data obtained independently at several international laboratories. The mechanisms field generation are analyzed considered as a function intensity spectral range emissions they produce. major emphasis is put on GHz frequency domain, which most...
A model providing an accurate estimate of the charge accumulation on surface a metallic target irradiated by high-intensity laser pulse fs--ps duration is proposed. The confirmed detailed comparisons with specially designed experiments. Such useful for understanding electromagnetic emission and quasistatic magnetic field generation in laser-plasma interaction
Recent experiments are showing possibilities to generate strong magnetic fields on the excess of 500 T with high-energy nanosecond laser pulses in a compact setup capacitor connected single turn coil. Hot electrons ejected from plate (cathode) collected at other (anode), thus providing source current However, physical processes leading generation currents exceeding hundreds kiloamperes such laser-driven diode not sufficiently understood. Here we present critical analysis previous results and...
A model of target charging in interaction with an intense short laser pulse is revised. It provides estimates the current energetic electrons escaping and total accumulated electric charge as a function characteristics thickness. Comparisons experimental data show performance, particular, case targets thinner than mean-free path electrons.
We investigate the properties of magnetic islands arising from tearing instabilities that are driven by an interchange turbulence. find such possess a specific signature permits identification their origin. demonstrate persistence small scale turbulence maintains mean pressure profile, whose characteristics makes it possible to discriminate between those due unfavourable plasma current density gradient. also island poloidal turnover time, in steady state, is independent levels and energy...
Pattern formation, observed experimentally in a radio-frequency plasma annular geometry, and characterized by azimuthal symmetry breaking of the parameters, is reported. The modulation increases with increasing pressure range 1--300 Pa. These experimental observations are accurately described fluid model which transport coefficients computed from 0D Boltzmann kinetic equation. A linear stability analysis shows that unstable modulations develop at low intermediate pressures, following an...
HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not.The documents may come from teaching institutions in France abroad, public private centers.L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de scientifiques niveau recherche, publiés ou non, émanant des établissements d'enseignement recherche français étrangers, laboratoires publics privés. Physics chromatic...
Higher order asymptotic matching procedure is developed to derive the nonlinear equation for saturated magnetic island with symmetric profile of equilibrium current. The theory extends previous results include higher effects such as modification current and asymmetry in boundary conditions outer region. It shown that due a finite width region, magnitude flux at rational surface different from value found solution, resulting suppression growth values Δ′ parameter.
The nonlinear properties of a turbulence driven magnetic island (TDMI) are investigated. Starting from minimal magnetohydrodynamic fluid model that provides for the generation TDMI and using scale separation arguments along with numerical simulation findings, we elucidate links between transport such islands characteristic features small turbulence. We also explain phenomenon partial pressure flattening inside TDMI.
The evolution of the radial profile rotation a weakly magnetized plasma column is investigated experimentally in radio-frequency argon at low pressure when strong electron current emitted by large emissive cathodes. Current injection from cathodes over background (with density few $10^{18}\ \textrm {m}^{-3}$ ) characterized. Radial scans ion velocity show that continuous control may be obtained using two spatial configurations for locations (either centre or edge column). results electric...
Abstract The characteristics of laser driven proton beams can be efficiently controlled and optimised by employing a recently developed helical coil technique, which exploits the transient self-charging solid targets irradiated intense pulses. Here we demonstrate well collimated (<1° divergence) narrow bandwidth (~10% energy spread) beamlet ~10 7 particles at 10 ± 0.5 MeV obtained irradiating with few joules, sub-ps pulses an intensity ~2 × 19 W cm −2 . experimental data are in good...
For the first time, a global model of electromagnetic pulse (EMP) emission connects charge separation in laser target to quantitative measurements field. We present frequency-domain dipole antenna which predicts quantity accumulated as well EMP amplitude and frequency. The is validated against from several high-intensity facilities, providing insight into physics informing design next-generation ultra-intense facilities. proportional total on target, but we demonstrate that it not directly...
The nonlinear evolution of magnetic islands is investigated by means numerical simulations. growth and saturation the island are shown to depend not only on asymptotic tearing mode stability parameter Δ′ but also initial global current profile. Presence external sheets leads formation different state for same value Δ′. It found that flow vorticity generated interacting an important feature nonlocal interactions effects in dynamics.
The nonlinear dynamics of a turbulence driven magnetic island (TDMI) is investigated numerically in reduced magnetohydrodynamic fluid model. significance identifying characteristic signature TDMI for its experimental observation discussed. principal focus our simulations on the nature pressure profile flattening inside TDMI, and we show that, agreement with analytical predictions, partial occurs when size exceeds critical value that function small scale interchange dynamics. We also present...
We investigate, through extensive 3D magneto-hydro-dynamics numerical simulations, the nonlinear excitation of a large scale magnetic island and its dynamical properties due to presence small-scale turbulence. Turbulence is induced by steep pressure gradient in edge region [B. D. Scott, Plasma Phys. Controlled Fusion 49, S25 (2007)], close separatrix tokamaks where there an X-point configuration. find that quasi-resonant localized interchange modes at plasma can beat together produce...
Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation A. Poyé, O. Agullo, Smolyakov, S. Benkadda, X. Garbet; Dynamics of magnetic islands in large Δ′ regimes. Phys. Plasmas 1 February 2014; 21 (2): 020705. https://doi.org/10.1063/1.4867065 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search...
An investigation of the electromagnetic (EM) pulse produced by high intensity laser-solid interactions has been carried out employing proton probing technique. Laser parameters including energy, duration, and were varied to investigate influence on EM amplitude. The data reveal that amplitude depends incident laser energy duration. optimum length for a given is found be close 100 fs. net charge associated with traveling dependent intensity, in good agreement semiempirical model....
The amplification of a turbulence driven seed magnetic island by the bootstrap current is investigated numerically in reduced magnetohydrodynamic model as possible additional channel for excitation and development neoclassical tearing mode (NTM) tokamak. novel mechanism such an involves two-step process, namely, formation due to nonlinear beating interchange modes followed leading large saturated island. Our study indicates that level controls both critical size size.
Quasi-static magnetic-fields up to $800\,$T are generated in the interaction of intense laser pulses ($500\,$J, $1\,$ns, $10^{17}\,$W/cm$^2$) with capacitor-coil targets different materials. The reproducible magnetic-field peak and rise-time, consistent pulse duration, were accurately inferred from measurements GHz-bandwidth inductor pickup coils (B-dot probes). Results Faraday rotation polarized optical light deflectometry energetic proton beams B-dot probe at early stages target charging,...
To simulate traveling-wave tubes (TWTs) in time domain and more generally the wave-particle interaction vacuum devices, we developed DIscrete MOdel with HAmiltonian approach (dimoha) as an alternative to current particle-in-cell (PIC) frequency approaches. Indeed, it is based on a longitudinal N-body Hamiltonian satisfying Maxwell's equations. Advantages of dimoha comprise: (i) allows arbitrary waveform (not just field envelope), including continuous (CW), multiple carriers or digital...
The saturation of magnetic islands is studied numerically for the current profiles with a finite gradient at rational surface. It shown that results such simulations are in good agreement analytical theory presented part I. effects plasma viscosity and not to affect final state islands.