A5052428976- Magnetic confinement fusion research
- Nuclear Physics and Applications
- Nuclear reactor physics and engineering
- Fusion materials and technologies
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Radiation Detection and Scintillator Technologies
- Ionosphere and magnetosphere dynamics
- Nuclear Materials and Properties
- Laser-Plasma Interactions and Diagnostics
- Atomic and Subatomic Physics Research
- Nuclear Engineering Thermal-Hydraulics
- Nuclear and radioactivity studies
- Plasma Diagnostics and Applications
- Particle Detector Development and Performance
- Nuclear physics research studies
- Solar and Space Plasma Dynamics
- Laser-induced spectroscopy and plasma
- Quantum, superfluid, helium dynamics
- Particle physics theoretical and experimental studies
- Astro and Planetary Science
- Neural Networks and Applications
- Radioactive contamination and transfer
- Atomic and Molecular Physics
- Radioactivity and Radon Measurements
Swedish Defence Research Agency
2023
Uppsala University
2011-2022
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2016-2020
Royal Military Academy
2020
CEA Cadarache
2020
Culham Science Centre
2007-2019
Culham Centre for Fusion Energy
2009-2016
European Incoherent Scatter Scientific Association
2012
Institute of Plasma Physics
2007
University of Milano-Bicocca
2007
Remarkable progress has been made in diagnosing energetic particle instabilities on presentday machines and establishing a theoretical framework for describing them.This overview describes the much improved diagnostics of Alfvén modelling tools developed world-wide, discusses interpreting observed phenomena.A multi-machine comparison is presented giving information performance both different plasma conditions outlining expectations ITER based our present knowledge.
Observations made in a JET experiment aimed at accelerating deuterons to the MeV range by third harmonic radiofrequency (RF) heating coupled into deuterium beam are reported.Measurements based on set of advanced neutron and gamma-ray spectrometers that, for first time, observe plasma simultaneously along vertical oblique lines sight.Parameters fast ion energy distribution, such as high cut-off deuteron distribution function RF coupling constant, determined from data within uniform analysis...
We demonstrate the measurement of a 2D MeV-range ion velocity distribution function by velocity-space tomography at JET. Deuterium ions were accelerated into third harmonic cyclotron resonance heating. made measurements with three neutron emission spectrometers and high-resolution γ-ray spectrometer detecting γ-rays released in two reactions. The tomographic inversion based on these five spectra is excellent agreement numerical simulations ASCOT–RFOF SPOT–RFOF codes. length measured fast-ion...
The fast-ion distribution from third harmonic ion cyclotron resonance frequency (ICRF) heating on the Joint European Torus is studied using neutron emission spectroscopy with time-of-flight spectrometer TOFOR. energy dependence of fast deuteron function inferred measured spectrum neutrons born in DD fusion reactions, and compared theoretical models for ICRF heating. Good agreements between modelling measurements are seen clear features function, that due to finite Larmor radius resonating...
The energy spectrum of the neutron emission from beam–target reactions in fusion plasmas at Joint European Torus (JET) has been investigated. Different beam energies as well injection angles were used. Both measurements and simulations done. made with time-of-flight spectrometer TOFOR. Simulations based on first-principle calculations neutral deposition profiles fast ion slowing down plasma using code NUBEAM, which is a module TRANSP package. shape was seen to vary significantly depending...
Abstract High-resolution γ-ray measurements were carried out on the Joint European Torus (JET) in an experiment aimed at accelerating 4 He ions MeV range by coupling third harmonic radio frequency heating to injected beam. For first time, Doppler broadening of peaks from 12 C(d, pγ) 13 C and 9 Be(α, nγ) reactions was observed interpreted with dedicated Monte Carlo codes based detailed nuclear physics processes. Information confined deuteron energy distribution inferred, energies as high 6...
Recent JET experiments have been devoted to the study of (3He)–D plasmas involving radio frequency (RF) heating. This paper starts by discussing RF heating efficiency theoretically expected in such plasmas, covering both relevant aspects wave and particle dynamics. Then it gives a concise summary main conclusions drawn from recent that were either focusing on studying physics or adopting as tool plasma behavior. Depending minority concentration chosen, different physical phenomena are...
Ion cyclotron radio frequency (ICRF) heating can produce fast ion populations with energies reaching up to several megaelectronvolts. Here, we present unique measurements of distributions from an experiment 3rd harmonic ICRF on deuterium beams using neutron emission spectroscopy (NES). From the experiment, very high DD rates were observed, only modest external powers. This was attributed acceleration beam ions about 2–3 MeV, where reactivity is a par that DT reaction. The allowed for...
During the 2015-2016 JET campaigns many efforts have been devoted to exploration of high-performance plasma scenarios envisaged for DT operation in JET.In this paper we review various key recent hybrid discharges and model combined ICRF+NBI heating.These deuterium with beams had ICRF antenna frequency tuned match cyclotron minority H at centre tokamak coinciding second harmonic resonance D. The modelling takes into account synergy between NBI heating through D beam ions which allows us...
Fast ions in fusion plasmas often leave characteristic signatures the neutron emission from plasma. In this paper, we show how measurements can be used to study fast and give examples of physics results obtained on present day tokamaks. The focus is with dedicated spectrometers compact detectors each channel profile monitors. A measured spectrum analyzed several different ways, depending scenario under consideration. Gross features a ion energy distribution studied by applying suitably...
For the first time, neutron emission from JET plasmas heated with combined deuterium neutral beam injection and third harmonic ion cyclotron radio frequency heating have been studied spectroscopy (NES). Very high DD rates were observed only modest external powers, which was attributed to acceleration of ions energies about 2–3 MeV, where reactivity is on a par that DT reaction. Fast energy distributions derived analysis NES data confirm up around 3 in agreement theoretical predictions. The...
A detailed description of the 14 MeV neutron emission in plasmas heated by neutral beam injection has been carried out coupling Monte Carlo calculations spectrum with TRANSP modelling ion energy distributions. The model is used to study tritium experiments JET trace campaign for internal transport barrier (ITB) and H-mode discharges. For ITB discharges, measured well described using as input distribution calculated TRANSP. H mode discharges can be reproduced only if high tritons are lost...
Experiments on accelerating NBI-produced deuterium (D) beam ions from their injection energy of ∼110 keV up to the MeV range with 3rd harmonic ion cyclotron resonance heating were performed Joint European Torus [P. H. Rebut and B. E. Keen, Fusion Technol. 11, 13 (1987)]. A renewed set nuclear diagnostics was used for analysing fast D during sawtooth stabilization, monster crashes, excitation Alfvén eigenmodes (AEs) residing inside q = 1 radius. The measurements modeling nonlinear HAGIS code...
In this paper, the scattered and direct neutron fluxes in line of sight (LOS) TOFOR spectrometer at JET are simulated simulations compared with measurement results. The Monte Carlo code MCNPX is used simulations, a vessel material composition obtained from drawing office emission profiles calculated TRANSP beam ion density profiles. show that scattering wall has large effect on shape spectrum. Neutron source profile shapes as well radial vertical displacements LOS shown to only marginally...
Recent fast ion studies at JET involve cyclotron resonance frequency (ICRF) heating tuned to minority 3 He in cold deuterium plasmas, with beryllium evaporation the vessel prior session. During experiments, high-resolution neutron spectrometer TOFOR was used study energy spectrum of emitted neutrons. Neutrons energies up 10 MeV, not consistent expected from d(d,n) reactions, were observed. In this paper, we interpret these neutrons as a first-time observation 9 Be( He,n) 11 C tokamak plasma,...
This paper discusses the extension of 'three-ion' species ICRF technique for heating mixture plasmas using fast injected NBI ions as resonant 'third' species. In this scenario power is absorbed by beam in vicinity mode conversion layer where left-hand polarized RF electric field E+ strongly enhanced. The velocity distribution that have a Doppler-shifted resonance close to efficiently absorb and undergo acceleration. We show first experimental observations D-NBI H-D JET with ITER-like wall....
The MPRu is an upgrade of the magnetic proton recoil (MPR) neutron spectrometer that has been used for 14MeV DT measurements at JET during DTE1 (1997) and TTE (2003) campaigns. In this contribution principles MPR its will be presented. allows full range fusion relevant energies, 1.5–18MeV, including neutrons, now with significantly reduced background, also new high-quality 2.5MeV DD component. This improvement made possible by use a detector in combination custom-built transient recorder...
Radio frequency (RF) heating experiments have recently been conducted in JET (3He)–H plasmas. This type of plasmas will be used ITER's non-activated operation phase. Whereas a companion paper this same PPCF issue discuss the RF scenario's at half nominal magnetic field, documents performance full with fundamental cyclotron 3He as only possible ion scheme view foreseen ITER antenna bandwidth. Dominant electron global efficiencies between 30% and 70% depending on concentration were observed...
The fuel ion ratio (nt/nd) is of central importance for the performance and control a future burning fusion plasma, reliable measurements this quantity are essential ITER. This paper demonstrates method to derive core by comparing thermonuclear beam-thermal neutron emission intensities, using spectrometer. applied NBI heated deuterium tritium (DT) plasmas at JET, data from magnetic proton recoil trend in results consistent with Penning trap edge but there discrepancy absolute values,...