A5028780121- Magnetic confinement fusion research
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Ionosphere and magnetosphere dynamics
- Gyrotron and Vacuum Electronics Research
- Fusion materials and technologies
- Logic, Reasoning, and Knowledge
- Plasma Diagnostics and Applications
- Particle Accelerators and Free-Electron Lasers
- Laser-Plasma Interactions and Diagnostics
- Logic, programming, and type systems
- Advanced Algebra and Logic
- Nuclear reactor physics and engineering
- Game Theory and Applications
- Mathematics and Applications
- Dust and Plasma Wave Phenomena
- Nuclear Materials and Properties
- Lubricants and Their Additives
- Metal and Thin Film Mechanics
- Tribology and Lubrication Engineering
- Power System Optimization and Stability
- Diamond and Carbon-based Materials Research
- Nuclear Physics and Applications
- Pulsed Power Technology Applications
- Congenital Diaphragmatic Hernia Studies
Shibaura Institute of Technology
2003-2025
Kurashiki Central Hospital
2022
National Institute for Materials Science
1986-2011
Panasonic (Japan)
1976-2007
Toyo University
2004
Research Institute of Ceramics
2003
Honda (Japan)
2003
St. Marianna University School of Medicine
1993-2001
Japan Atomic Energy Agency
1978-2000
Honda (United States)
1992-1999
It is observed that the waves launched from a phased array antenna of four waveguides couple effectively with electrons under condition $\frac{{\ensuremath{\omega}}_{0}}{{\ensuremath{\omega}}_{1h}(0)}\ensuremath{\gtrsim}2.0$. This coupling generates rf-driven current, rather than heating bulk electrons, and current/rf-power ratio 110 A/kW was obtained rf power 125 kW radiated into plasma which included appreciable suprathermal electrons.
Experimental data are presented which show that during lower-hybrid, radio-frequency heating of the Princeton University adiabatic toroidal compressor tokamak, parametric instabilities excited, and ion correlates with presence spectra. A theoretical interpretation is presented.
Optical correlation-domain reflectometry (OCDR), widely recognized for its ability to pinpoint the locations and reflectivities of faulty connections other reflective points along optical fibers, offers advantages random accessibility, real-time operation, cost-effectiveness. In Brillouin OCDR, commonly employed distributed strain temperature sensing, a well-known challenge is trade-off between spatial resolution measurement range. To overcome this limitation, double-modulation scheme has...
Ion heating by irradiation of rf fields in the ion-cyclotron range frequencies is investigated using several diagnostic techniques. It shown that substantial bulk ions can be achieved this method.
Decay spectra during the rf heating were identified as parametric decay into cold lower-hybrid waves and ion-cyclotron at plasma surface. The instabilities absorbed some fraction of power, hence they affected heating. However, did not prevent penetration lower hybrid wave to center. Drastic reduction was obtained when resonant condition destroyed.
Results from the JFT−2a (DIVA) experiments made with a separatrix magnetic surface are described. The main conclusions are: (1) A is stably located inside material surface. (2) plasma enclosed in similar to that of conventional tokamak as far magnetohydrodynamic properties concerned. (3) Measured parameters column consistent those expected tokamak. (4) electron density and temperature scrape-off layer about ten times less than values at center column. (5) Heat particle fluxes divertor region...
In order to improve the safe handling and control of tritium for ITER fuel cycle, effective in situ accounting methods have been developed at Tritium Process Laboratory Japan Atomic Energy Research Institute under one ITER-EDA R&D tasks. The remote multilocation analysis process gases by an application laser Raman spectroscopy tested could provide a measurement hydrogen isotope with detection limit 0.3 kPa analytical periods 120 s. An inventory `self-assaying' storage bed 25 g capacity...
Results are presented of the first Lower Hybrid Current Drive (LHCD) experiments in JT-60. 2 MA RF driven current is successfully produced for time a reactor grade tokamak. The magnetic divertor works quite well eliminating impurities released by carrying fast electrons which have allowed generation relevant very low density plasma. efficiency defined as ηCD = eRIRF/PLH(1019 m−3 A·W−1), reaches values 0.8 to 1.7. NBI heating enhances drive factor 1.5, and LHCD improves confinement high power...
A multijunction launcher was designed and constructed to improve the directivity of launched waves with a narrow wave number spectrum by dividing each main waveguide into three secondary waveguides. The coupling characteristics agree fairly well theory, power up 2 MW obtained after few days conditioning. dependence current drive efficiency ηCD (= neIRFR/PLH) on studied changing phase difference between adjacent It found that high is interacting fast electrons as far plasma travel. maximum...
A Langmuir probe is used to study the plasma behaviour in scrape-off layer of JFT-2a, (a Tokamak with an axisymmetric divertor). The measurements reveal particle fluxes divertor and wall as well cross-field profiles density potential layer. On basis these measurements, diffusion coefficient efficiency are estimated. existence magnetic limiter also verified by method.
Neutral-beam injection experiments on ATC have resulted in net power deposited the plasma of up to 230 kW. The ions is large compared that from ohmic heating. For a variety beam and ion species, increase temperature proportional power.
Recent lower hybrid current drive (LHCD), and heating (LHH) experiments on JT-60 are reported. The product of neRpIRF approximately 12.5*1019 m-2 MA was achieved at the LH power 4.5 MW, CD efficiency, energy confinement, global balance heat load divertor plates were investigated in high LHCD plasmas. Nearly steady state H-mode discharges found during with two different frequency injections. Sawtooth suppression NB heated plasmas by have shown an improvement confinement near plasma center....
ICRF heating of impurity-free tokamak plasmas is studied in DIVA. The frequency fixed at 25 MHz, which a second-harmonic cyclotron deuteron with toroidal magnetic field 16.4 kG. BT and the ratio proton-to-deuteron density p are varied over ranges 12 ⩽ 19 kG 2 ⪅ 40%, respectively. most favourable ion obtained = 18 5 ∼ 10%. Ion temperature increases from 200 to 300 eV were measured by charge-exchange neutral analysis also spectroscopy, where 100 kW RF net power applied. results consistent...
Some experimental informations have been obtained concerning the particle and heat transport during lower hybrid heating in JFT-2 tokamak. The cross field coefficients are determined from plasma parameters a scrape-off layer, add losses to limiter wall also estimated experimentally. It is shown that heatting does not give serious effects on confinement, if effective ion performed successfully main plasma.
Beam acceleration by heating in the second-harmonic ion cyclotron range of frequency (ICRF) combination with hydrogen neutral beam injection (NBI) was investigated JT-60 tokamak. The energy spectra accelerated fast ions were measured a charge exchange analyser whose line sight intersected specific lines plasma core order to obtain required information. dependences tail temperature on various parameters (electron density, NBI power and toroidal phasing antenna) examined. Optimized conditions...