A5019766649- Magnetic confinement fusion research
- Fusion materials and technologies
- Ionosphere and magnetosphere dynamics
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Laser-Plasma Interactions and Diagnostics
- Plasma Diagnostics and Applications
- Nuclear reactor physics and engineering
- Solar and Space Plasma Dynamics
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Physics of Superconductivity and Magnetism
- Anomaly Detection Techniques and Applications
- Plasma Applications and Diagnostics
- Energetic Materials and Combustion
- Nuclear physics research studies
- Geophysics and Sensor Technology
- Flame retardant materials and properties
- Diamond and Carbon-based Materials Research
- Nuclear Physics and Applications
- Viral Infections and Vectors
- Fault Detection and Control Systems
- Computational Fluid Dynamics and Aerodynamics
- Astronomical Observations and Instrumentation
- Astrophysics and Star Formation Studies
National Agency for New Technologies, Energy and Sustainable Economic Development
2013-2025
National Academies of Sciences, Engineering, and Medicine
2024
Institute for the Science and Technology of Plasmas
2019-2024
University of Milano-Bicocca
2021-2022
National Research Council
2020-2021
Institute of Plasma Physics
2015-2019
École Polytechnique Fédérale de Lausanne
2016-2018
University of Milan
1991-2013
University of Sassari
2005
National Interuniversity Consortium of Materials Science and Technology
2005
Abstract Progress in physics understanding and theoretical model development of plasma transport confinement (TC) the ITPA TC Topical Group since publication ITER Physics Basis (IPB) document (Doyle et al 2007 Nucl. Fusion 47 S18) was summarized focusing on contributions to burning prediction control. This paper provides a general streamlined overview advances that were mainly led by joint experiments activities for last 15 years (see JEX/JA table appendix). starts with scientific strategy...
Abstract Plasmas with negative triangularity (NT) shape have been recently shown to be able achieve H-mode levels of confinement in L-mode, avoiding detrimental edge localised modes. Therefore, this plasma geometry is now studied as a possible viable option for future fusion reactor. Within framework, an NT under investigation the full power scenario Divertor Tokamak Test (DTT) facility, construction Italy, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">...
New H-mode regimes with high confinement, low core impurity accumulation, and small edge-localized mode perturbations have been obtained in magnetically confined plasmas at the Joint European Torus tokamak. Such are achieved by means of optimized particle fueling conditions input power, current, magnetic field, which lead to a self-organized state strong increase rotation ion temperature decrease edge density. An interplay between plasma regions leads reduced turbulence levels outward...
Abstract This paper presents a study on the dependence of ion temperature stiffness plasma main isotope mass in JET ITER-like wall and C discharges. To this aim, database H, D T shots is analyzed, including new dedicated shots, comparing experiments with lower higher power injected by NBI system. In order to characterize turbulence mass, three these discharges (two one D) same external heating scheme are studied detail interpreted gyrokinetic linear nonlinear simulations. The analysis...
Dedicated experiments to generate energetic D ions and fusion-born alpha particles were performed at the Joint European Torus (JET) with ITER-like wall (ILW). Using 3-ion radio frequency (RF) heating scenario, deuterium from neutral beam injection (NBI) accelerated in core of mixed plasmas higher energies ion cyclotron resonance (ICRF) waves, turn leading a core-localized source particles. The fast-ion distribution RF-accelerated D-NBI was controlled by varying ICRF NBI power ( 4–6 MW, 3–20...
An intensive integrated modelling work of the main scenarios new Divertor Tokamak Test (DTT) facility with a single null divertor configuration has been performed using first principle quasi-linear transport models, in support design device and definition its scientific programme. First results this on DTT (R0 = 2.14 m, 0.65 m) are presented here along outcome gyrokinetic simulations used to validate reduced models range parameters. As result work, heating mix defined, size increased R0 2.19...
Abstract The dimensionless isotope mass scaling experiment between pure Deuterium and Tritium plasmas with matched <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mi>ρ</mml:mi> <mml:mo>∗</mml:mo> </mml:msup> </mml:math> , <mml:mi>ν</mml:mi> β n q <mml:msub> <mml:mi>T</mml:mi> <mml:mi>e</mml:mi> </mml:msub> <mml:mrow> <mml:mo>/</mml:mo> </mml:mrow> <mml:mi>i</mml:mi> has been achieved in JET L-mode dominant electron heating (NBI+ohmic) conditions....
Abstract Negative triangularity (NT) scenarios in TCV have been compared to positive (PT) using the same plasma shapes foreseen for divertor tokamak test operations. The experiments provided a NT/PT L-mode pair and PT H-mode with different heating mixes. Regardless of mix, NT L-modes always reached higher values pressure respect power recovered central heated up twice injected power. experimental analysis shows that this enhanced performance is due larger temperature density gradients close...
Abstract Previous studies with first-principle-based integrated modelling suggested that electron temperature gradient (ETG) turbulence may lead to an anti-gyroBohm isotope scaling in JET high-performance hybrid H-mode scenarios. A dedicated comparison study against higher-fidelity invalidates this claim. Ion-scale magnetic field perturbations included, can match the power balance fluxes within error margins. Multiscale gyrokinetic simulations from two distinct codes produce no significant...
Fusion performance in tokamaks depends on the core and edge regions as well their nonlinear feedbacks.The achievable degree of confinement under constraints power handling presence a metallic wall is still an open question.Therefore, any improvement temperature density peaking crucial for achieving target performance.This has motivated further progress understanding turbulent transport mechanisms, to help scenario development present devices improve predictive tools ITER operations.In last...
Gamma-ray spectroscopy (GRS) has become an established technique to determine properties of the distribution function energetic particles in MeV range, which are fast ions from heating and fusion reactions or runaway electrons born disruptions. In this paper we present a selection recent results where GRS is key investigate physics range particles. These radio-frequency experiments, theoretical models can be tested with unprecedented degree accuracy, disruption mitigation studies, sheds...
Particle transport has been extensively studied by performing several dimensionally matched collisionality scans in various plasma scenarios JET.Gas puff modulation technique developed with high quality time-dependent density profile measurements to determine particle coefficients.Density peaking found increase decreasing * all H-mode while L-mode, no dependency was found.The experimentally determined coefficients suggest that NBI fueling is main contributor the observed H-mode.This...
Abstract The paper presents experimental and modelling results of a comparison negative (NT) positive (PT) triangularity ASDEX Upgrade (AUG) discharges using the plasma shapes presently foreseen in DTT tokamak, under construction Italy. This work is part broader effort investigation to understand whether good properties observed NT scenarios DIII-D TCV may be extrapolated device more generally DEMO future operations. have shown practical gain running these AUG plasmas with only ECRH mixed...
Abstract This paper is dealing with the physics basis used for design of Divertor Tokamak Test facility (DTT), under construction in Frascati (DTT 2019 DTT interim report (2019)) Italy, and description main target plasma scenarios device. The goal will be study power exhaust, intended as a fully integrated core-edge problem, eventually to propose an optimized divertor European DEMO plant. approach described their features are reported, by using simulations performed state-of-the-art codes...
Abstract This is an overview of the theoretical understanding so-called isotope effect in JET hydrogen versus deuterium plasmas. Experimentally, weak to moderate deviations from naive GyroBohm scaling expectations are found for core heat transport L and H-modes. The physical mechanisms behind such analysed framework gyrokinetic theory. In case particle transport, effects mostly plasma edge where density higher than general, both thermal energy confinement increase with increasing main ion...
Abstract Experiments, gyrokinetic simulations and transport predictions were performed to investigate if a negative triangularity (NT) L-mode option for the Divertor Tokamak Test (DTT) full-power scenario would perform similarly positive (PT) H-mode reference scenario, avoiding harmful edge localized modes (ELMs). The show that beneficial effect of NT coming from edge/scrape-off layer (SOL) region <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow>...
Reducing the uncertainty on physical input parameters derived from experimental measurements is essential towards improving reliability of gyrokinetic turbulence simulations. This can be achieved by introducing constraints. Amongst them, zero particle flux condition considered here. A first attempt also made to match as well ion/electron heat ratio. procedure applied analysis a particular Tokamak à Configuration Variable discharge. detailed reconstruction hyper-surface in multi-dimensional...
The 24 MW ITER electron cyclotron (EC) heating and current drive (H CD) system, operating at 170 GHz, consists of one equatorial four upper launchers (UL). main task the UL will be control magneto-hydrodynamic activity such as neoclassical tearing modes (NTMs) q = 3/2 2 surfaces sawteeth 1, but it also needed for profile tailoring in advanced scenarios to assist plasma break-down L- H-mode transition. Moreover, is required effective both when operate nominal reduced magnetic field magnitude.
The excitation mechanism for low-n edge harmonic oscillations in quiescent H-mode regimes is identified analytically. We show that the combined effect of diamagnetic and poloidal magnetohydrodynamic flows, with constraint a Doppler-like ion flow, leads to stabilization short wavelength modes, allowing perturbation grow. analysis, performed tokamak toroidal geometry, includes effects large pressure gradients, associated local flattening safety factor sheared parallel E×B rotation, vacuum...
A new dispersion relation, and associated stability criteria, is derived for low-n external kink infernal modes, applied to modelling the properties of quiescent H-mode like regimes. The analysis, performed in toroidal geometry with large edge pressure gradients a local flattening safety factor, includes pedestal, sheared rotation vacuum region separating plasma from an ideal metallic wall. kink-infernal modes found here exhibit similarities experimentally observed harmonic oscillations.
Abstract A benchmark of the reduced quasi-linear models QuaLiKiz and TGLF with GENE gyrokinetic simulations has been performed for parameters corresponding to a JET high performance hybrid pulse in deuterium. Given importance study such advanced scenarios view ITER DEMO operations, dependence transport on ion isotope mass also assessed, by repeating changing tritium. agrees better linear spectra flux levels. However, concerning dependence, only reproduces radial trend basically gyro-Bohm...
We consider the construction of asymptotic solutions Maxwell's equations for a diffracting wave beam in high frequency limit and address description energy flux transported by beam. With this aim, complex eikonal method is applied. That generalization standard geometrical optics which phase function assumed to be valued, with non-negative imaginary part accounting finite width cross section. In framework, we propose an argument simplifies significantly analysis transport equation field...
The problem of pressure driven infernal type perturbations near the plasma edge is addressed analytically for a circular limited tokamak configuration which presents an flattened safety factor. separated from metallic wall, either ideally conducting or resistive, by vacuum region. dispersion relation such types instabilities derived and discussed two classes equilibrium profiles mass density.
Tokamaks dominated by electron heating like ITER could possibly suffer from the consequences of an temperature gradient (ETG) mode destabilisation, which develop a turbulent heat flux capable setting upper limit to achievable peaking, resulting in degradation fusion performances.An effort is carried out paper collect and compare results dedicated plasma discharges performed during last years at three major European tokamaks, TCV, AUG JET, analysing transport for cases presumably compatible...