A5021193921- Magnetic confinement fusion research
- Laser-Plasma Interactions and Diagnostics
- Ionosphere and magnetosphere dynamics
- Superconducting Materials and Applications
- Fusion materials and technologies
- Plasma Diagnostics and Applications
- Particle accelerators and beam dynamics
- Laser-induced spectroscopy and plasma
- Advanced X-ray Imaging Techniques
- X-ray Spectroscopy and Fluorescence Analysis
- Atomic and Molecular Physics
- Solar and Space Plasma Dynamics
- Nuclear Physics and Applications
- Atomic and Subatomic Physics Research
- Laser-Matter Interactions and Applications
- Particle Accelerators and Free-Electron Lasers
- Laser Design and Applications
- Nuclear reactor physics and engineering
- High-pressure geophysics and materials
- Nuclear Materials and Properties
- Medical Imaging Techniques and Applications
- Metal and Thin Film Mechanics
- Radiation Detection and Scintillator Technologies
- Electron and X-Ray Spectroscopy Techniques
- Mass Spectrometry Techniques and Applications
Johns Hopkins University
2015-2025
Extreme Light Infrastructure - Nuclear Physics
2016-2025
Horia Hulubei National Institute for R and D in Physics and Nuclear Engineering
2016-2025
National Institute for Laser Plasma and Radiation Physics
2019
Princeton Plasma Physics Laboratory
1997-2016
Oak Ridge National Laboratory
2003-2016
National Agency for New Technologies, Energy and Sustainable Economic Development
2016
University of Padua
2016
Auburn University
2016
University of Wisconsin–Madison
2016
The European Strategy Forum on Research Infrastructures (ESFRI) has selected in 2006 a proposal based ultra-intense laser fields with intensities reaching up to 1022-1023 W cm-2 called 'ELI' for Extreme Light Infrastructure. construction of large-scale laser-centred, distributed pan-European research infrastructure, involving beyond the state-of-the-art ultra-short and technologies, received approval funding 2011-2012. three pillars ELI facility are being built Czech Republic, Hungary...
The emergence of a new era reaching beyond current state-of-the-art ultrashort and ultraintense laser technology has been enabled by the approval around € 850 million worth structural funds in 2011–2012 European Commission for installation Extreme Light Infrastructure (ELI). ELI project consists three pillars being built Czech Republic, Hungary, Romania. This challenging proposal is based on recent technical progress allowing fields which intensities will soon be as high I0 ∼ 1023 W cm−2....
Abstract The spherical tokamak (ST) is a leading candidate for Fusion Nuclear Science Facility (FNSF) due to its compact size and modular configuration. National Spherical Torus eXperiment (NSTX) MA-class ST facility in the US actively developing physics basis an ST-based FNSF. In plasma transport research, experiments exhibit strong (nearly inverse) scaling of normalized confinement with collisionality, if this trend holds at low high fusion neutron fluences could be achievable very...
Research in NSTX has been conducted to establish spherical torus plasmas be used for high β, auxiliary heated experiments. This device a major radius R0 = 0.86 m and midplane halfwidth of 0.7 m. It operated with toroidal magnetic field B0 ⩽ 0.3 T Ip 1.0 MA. The evolution the plasma equilibrium is analysed between discharges an automated version EFIT code. Limiter, double null lower single diverted configurations have sustained several energy confinement times. stored reached 92 kJ (βt 17.8%)...
The National Spherical Torus Experiment (NSTX) has demonstrated the advantages of low aspect ratio geometry in accessing high toroidal and normalized plasma beta, βN ≡ 108⟨βt⟩ aB0/Ip. Experiments have reached βt = 39% 7.2 through boundary profile optimization. High plasmas can exceed ideal no-wall stability limit, βNno−wall, for periods much greater than wall eddy current decay time. Resistive mode (RWM) physics is studied to understand stabilization these plasmas. spectrum unstable RWMs...
The NSTX operates at low aspect ratio (R/a ∼ 1.3) and high beta (up to 40%), allowing tests of global confinement local transport properties that have been established from higher devices. plasmas are heated by up 7 MW deuterium neutral beams with preferential electron heating as expected for ITER. Confinement scaling studies indicate a strong BT dependence, current dependence is weaker than observed ratio. Dimensionless experiments increase in decreasing collisionality weak degradation...
A high-resolution radiographic method for soft tissues in the small joints of hand would aid study and treatment rheumatoid arthritis (RA) osteoarthritis (OA), which often attacks these joints. Of particular interest be imaging with <100 µm resolution joint cartilage, whose integrity is a main indicator disease. Differential phase-contrast (DPC) or refraction-based x-ray Talbot grating interferometers could provide such method, since it enhances tissue contrast can implemented conventional...
Using three-dimensional kinetic simulations, we examine the emission of collimated $\ensuremath{\gamma}$-ray beams from structured laser-irradiated targets with a prefilled cylindrical channel and its scaling laser power (in multi-PW range). The is increased by increasing energy size focal spot while keeping peak intensity fixed at $5\ifmmode\times\else\texttimes\fi{}{10}^{22}\phantom{\rule{0.2em}{0ex}}\mathrm{W}/{\mathrm{cm}}^{2}$. radius proportionally to accommodate change in size....
High power lasers have proven being capable to produce high energy gamma rays, charged particles and neutrons induce all kinds of nuclear reactions. At ELI, the studies with will enter for first time into new domains intensities.
Recent experiments in the Current Drive Experiment-Upgrade (CDX-U) provide a first-ever test of large area liquid lithium surfaces as tokamak first wall to gain engineering experience with metal and investigate whether very low recycling plasma regimes can be accessed walls. The CDX-U is compact (R = 34 cm, 22 Btoroidal 2 kG, IP 100 kA, Te(0)∼ eV, ne(0) ∼ 5 × 1019 m−3) spherical torus at Princeton Plasma Physics Laboratory. A toroidal pool limiter an 2000 cm2 (half total limiting surface)...
A wide variety of fast ion driven instabilities are excited during neutral beam injection (NBI) in the National Spherical Torus Experiment (NSTX) [Nucl. Fusion 40, 557 (2000)] due to large ratio velocity Alfvén velocity, Vfast∕VAlfvén, and high beta. The Vfast∕VAlfvén ITER 39, 2137 (1999)] NSTX is comparable. modes can be divided into three categories: chirping energetic particle (EPM) frequency range 0 120kHz, toroidal eigenmodes (TAE) with a 50kHz 200kHz, compressional global (CAE GAE,...
We report the observation of a correlation between shear Alfv\'en eigenmode activity and electron transport in plasma regimes where temperature gradient is flat, thus drive for microinstabilities absent. Plasmas having rapid central show intense, broadband global (GAE) 0.5--1.1 MHz range, while plasmas with low are essentially GAE-free. The first theoretical assessment GAE-electron connection indicates that overlapping modes can resonantly couple to bulk thermal electrons induce their...
High-power laser systems have opened new frontiers in scientific research and revolutionized various fields, offering unprecedented capabilities for understanding fundamental physics allowing unique applications. This paper details the successful commissioning of 1 PW experimental area at Extreme Light Infrastructure–Nuclear Physics (ELI-NP) facility Romania, using both available arms. The setup featured a short focal parabolic mirror to accelerate protons through target normal sheath...
Global magnetohydrodynamic (MHD) stability limits in the National Spherical Torus Experiment (NSTX) have increased significantly recently due to a combination of device and operational improvements. First, more routine H-mode operation with broadened pressure profiles allows access higher normalized β lower internal inductance. Second, correction poloidal field coil induced error-field has largely eliminated locked tearing modes during normal maximum achievable β. As result these...
Saturated internal kink modes have been observed in many of the highest toroidal β discharges National Spherical Torus Experiment (NSTX). These often cause rotation flattening plasma core, can degrade fast-ion confinement and some cases contribute to complete loss angular momentum stored energy. Characteristics are measured using soft x-ray, kinetic profile magnetic diagnostics. Toroidal flows approaching Alfvenic speeds, island pressure peaking enhanced viscous diamagnetic effects...
A motional Stark effect diagnostic has been utilized to reconstruct the parallel current density profile in a spherical-torus plasma for first time. The measured compares favorably with neoclassical theory when no large-scale magnetohydrodynamic instabilities are present plasma. However, anomaly is observed during saturated interchange-type instability activity. This apparent can be explained by redistribution of neutral beam injection drive and represents observation causing such...
The onset conditions for the m / n = 2/1 neoclassical tearing mode are studied in terms of drive, triggering instabilities, and toroidal rotation or shear, spherical torus NSTX (Ono M. et al 2000 Nucl. Fusion 40 557 ). There three typical these modes, given order increasing drive required onset: by energetic particle edge localized modes cases where appear to grow without a trigger. In all cases, increases with implying stabilizing effect from shear.
We use 3D simulations to demonstrate that high-quality ultrarelativistic electron bunches can be generated on reflection of a twisted laser beam off plasma mirror. The unique topology the with twist index $|l|=1$ creates an accelerating structure dominated by longitudinal electric and magnetic fields in near-axis region. show field is essential for creating train dense monoenergetic bunches. For 6.8 PW laser, energy reaches 1.6 GeV spread 5.5%. bunch duration 320 as, its charge 60 pC,...
Research on the stability of spherical torus plasmas at and above no-wall beta limit is being addressed National Spherical Torus Experiment [M. Ono et al., Nucl. Fusion 40, 557 (2000)], that has produced low aspect ratio plasmas, R/a∼1.27 plasma current exceeding 1.4 MA with high energy confinement (TauE/TauE_ITER89P&gt;2). Toroidal normalized have exceeded 25% 4.3, respectively, in q∼7 plasmas. The observed to increase then saturate increasing li. factor βN/li reached 6, limited by...
H-mode operation plays a crucial role in National Spherical Torus Experiment (NSTX) research, allowing higher beta limits due to reduced plasma pressure peaking, and long pulse high bootstrap current fraction. Here, new results are presented the areas of edge localized modes (ELMs), pedestal physics power threshold studies. ELMs several types as reported by aspect ratio tokamaks have been observed: (1) large, Type I ELMs, (2) intermediate-sized III (3) tiny ELMs. Many performance discharges...
The major objective of the National Spherical Torus Experiment (NSTX) is to understand basic toroidal confinement physics at low aspect ratio and high βT in order advance spherical torus (ST) concept. In do this, NSTX utilizes up 7.5 MW neutral beam injection, 6 harmonic fast waves (HHFWs), it operates with plasma currents 1.5 MA elongations 2.6 a field 0.45 T. New facility, diagnostic modelling capabilities developed over past two years have enabled research team make significant progress...
Extreme Light Infrastructure-Nuclear Physics (ELI-NP), to become operational in 2019, is a new Research Center built Romania that will use extreme electromagnetic fields for nuclear physics research. The ELI-NP facility combine two large equipments with state-of-the-art parameters, namely 2 × 10 PW high-power laser system and very brilliant gamma-beam delivering beams energies up 19.5 MeV. systems under construction typical proposed first-phase experiments are described.
Spherical tokamaks have relatively low toroidal field which means that the fast-ion Larmor radius is large (ρfi&gt;0.04 ap) and fast ion velocity much greater than Alfvén speed (Vfi&gt;2 VAlfvén). This regime of a in driven instabilities are potentially virulent. It therefore an important goal present proof-of-principle spherical to evaluate role confinement. paper presents first observations losses tokamak resulting from energetic particle modes. Two classes responsible for losses....