A5049799692- Magnetic confinement fusion research
- Ionosphere and magnetosphere dynamics
- Particle accelerators and beam dynamics
- Fusion materials and technologies
- Lightning and Electromagnetic Phenomena
- Superconducting Materials and Applications
- Laser-Plasma Interactions and Diagnostics
- Plasma Diagnostics and Applications
- Electromagnetic Simulation and Numerical Methods
- X-ray Spectroscopy and Fluorescence Analysis
- Geophysical Methods and Applications
- Thermal Analysis in Power Transmission
- Atomic and Molecular Physics
- Electromagnetic Compatibility and Measurements
- Nuclear Physics and Applications
- Solar and Space Plasma Dynamics
- Microwave Imaging and Scattering Analysis
- Electromagnetic Scattering and Analysis
- Electromagnetic Compatibility and Noise Suppression
- Laser-induced spectroscopy and plasma
- High voltage insulation and dielectric phenomena
- Electrical Fault Detection and Protection
- Probabilistic and Robust Engineering Design
- Nuclear reactor physics and engineering
- Metal and Thin Film Mechanics
University of Split
2012-2022
Max Planck Society
1978-2017
Max Planck Innovation
2002-2017
Max Planck Institute for Plasma Physics
1980-2003
Princeton Plasma Physics Laboratory
1987-2002
Princeton University
1988-2002
Oak Ridge National Laboratory
1986-1994
Fusion Academy
1994
Fusion (United States)
1994
National Agency for New Technologies, Energy and Sustainable Economic Development
1994
Strong magnetohydrodynamic activity has been observed in PDX neutral-beam-heated discharges. It occurs for ${\ensuremath{\beta}}_{T}q>~0.045$ and is associated with a significant loss of fast ions drop neutron emission. As much as 20%-40% the beam heating power may be lost. The instability repetitive bursts oscillations \ensuremath{\le} 1 msec duration at 1-6-msec intervals. dubbed "fishbone instability" from its characteristic signature on Mirnov coils.
Neutral-beam heating of plasmas in the Tokamak Fusion Test Reactor at low preinjection densities [${n}_{e}$(0)\ensuremath{\simeq}${10}^{19}$ ${\mathrm{m}}^{\mathrm{\ensuremath{-}}3}$] were characterized by ${T}_{e}$(0)=6.5 keV, ${T}_{i}$(0)=20 ${n}_{e}$(0)=7\ifmmode\times\else\texttimes\fi{}${10}^{19}$ ${\mathrm{m}}^{\mathrm{\ensuremath{-}}3}$, ${\ensuremath{\tau}}_{E}$=170 msec, ${\ensuremath{\beta}}_{\mathrm{theta}}$=2, and a d(d,n${)}^{3}$He neutron emission rate ${10}^{16}$...
K\ensuremath{\alpha} x-ray spectra of heliumlike titanium, Ti xxi, from Tokamak Fusion Test Reactor (TFTR) plasmas have been observed with a high-resolution crystal spectrometer and used as diagnostic central plasma parameters. The data allow detailed comparison recent theoretical predictions for the xxi lines associated satellite spectrum in wavelength range 2.6000 to 2.6400 A\r{}. Improved values excitation rate coefficients resonance line, intercombination lines, forbidden new results on...
Stationary discharges with $H$-mode edge and internal transport barrier for energy, momentum, particle have been obtained on ASDEX Upgrade. At a line averaged density of $4\ifmmode\times\else\texttimes\fi{}{10}^{19}{\mathrm{m}}^{\ensuremath{-}3}$ an $H$ factor ${H}_{\mathrm{ITER}89\ensuremath{-}P}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2.4$ ${\ensuremath{\beta}}_{N}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2$ could be maintained 6 s corresponding to 40 confinement times,...
The early phase of the neoclassical (3,2) + (2,2) tearing mode at ASDEX Upgrade has been investigated in order to study seed island. Sawtooth crashes or fishbones can trigger this mode, and few cases it appeared spontaneously.
High-resolution spectra of the Ly-${\ensuremath{\alpha}}_{1}$ and Ly-${\ensuremath{\alpha}}_{2}$ lines hydrogenlike titanium, Ti XXII, associated dielectronic satellites which are due to transitions $1snl\ensuremath{-}2pnl$ with $n\ensuremath{\ge}2$, have been observed from tokamak discharges auxiliary ion-cyclotron heating central electron temperatures 2 keV densities 8\ifmmode\times\else\texttimes\fi{} ${10}^{13}$ ${\mathrm{cm}}^{\ensuremath{-}3}$ on Princeton Large Torus (PLT). The data...
During tangential neutral-beam injection into the PBX tokamak, bursts of two types instabilities are observed. One instability occurs in frequency range 120-210 kHz and other oscillates predominantly near bulk plasma rotation (20-30 kHz). Both correlate with drops neutron emission charge-exchange neutral flux, indicating that beam ions removed from center by instabilities. The central losses comparable to induced fishbone during perpendicular injection.
The bremsstrahlung emission from the PLT tokamak during lower-hybrid current drive has been measured as a function of angle between magnetic field and direction. is peaked strongly in forward direction, indicating strong anisotropy electron velocity distribution. data demonstrate existence nearly flat tail distribution, which extends out to approximately 500 keV interpreted plateau created by Landau damping waves.
The βp value for the onset of neoclassical (3, 2) tearing mode at ASDEX Upgrade is found to be proportional ion gyro-radius as proposed in polarization model. This scaling law has been proven by varying temperature, magnetic field and mass plasma ions.
High confinement [with $H\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1$, ITERH- $98(y,2)$] at ${\ensuremath{\beta}}_{N}\ensuremath{\approx}2.3$ has been found in ASDEX Upgrade discharges with existing $(m,n)\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}(3,2)$ neoclassical tearing modes (NTMs). The reason for the high ${\ensuremath{\beta}}_{N}$ values is a transition of NTMs into so-called frequently interrupted regime. In this regime, NTM growth by sudden drops amplitude. Because...
Application of Ion Bernstein Wave Heating (IBWH) into the Princeton Beta Experiment-Modification (PBX-M) [Phys. Fluids B 2, 1271 (1990)] tokamak stabilizes sawtooth oscillations and generates peaked density profiles. A transport barrier, spatially correlated with IBWH power deposition profile, is observed in core IBWH-assisted neutral beam injection (NBI) discharges. precursor to fully developed barrier seen soft x-ray data during edge localized mode (ELM) activity. Sustained operation...
The first probe measurements of edge turbulence and transport in a neutral beam induced high confinement mode (H-mode) are reported. A strong negative radial electric field is directly observed H-mode. transient suppression normalized ion saturation floating potential fluctuation levels occurs at the low to (L–H) transition, followed by recovery near (L-mode) levels. average poloidal wave number wave-number spectral width decreased, correlation between fluctuating density reduced....
The highly indented plasmas of the PBX-M tokamak experiment [Plasma Physics and Controlled Nuclear Fusion Research (IAEA, Vienna, 1989), Vol. 1, p. 97] have reached plasma regimes both high volume-averaged beta (βt), high-beta poloidal (βp), show evidence suppression external surface modes by passive stabilizing system. Values βt up to 4.0 I/aB (% MA/m T) with Ti(0)≊4 keV been obtained. A magnetohydrodynamic analysis βp=2.0 indicates that these are near threshold second stability regime....
The TFTR tokamak has reached its original machine design specifications (Ip=2.5 MA and BT=5.2 T). Recently, the D degrees neutral beam heating power been increased to 6.3 MW. By operating at low plasma current (Ip approximately=0.8 MA) density (ne approximately=1*1019 m-3), high ion temperatures (9+or-2 keV) rotation speeds (7*105 m/s) have achieved during injection. At opposite extreme, pellet injection into plasmas used increase line-average 8*1019 m-3 central 1.6*1020 m-3. This wide range...
In this paper, a generalized form of telegrapher's equations for electromagnetic field coupling to buried wires is derived. The presented approach based on thin-wire antenna theory. effect dissipative half-space taken into account via the reflection/transmission coefficient approximation. conductor losses can be surface impedance per unit length. derived are treated numerically Galerkin-Bubnov indirect boundary element method. Numerical results induced current along wire, and compared with...
The boundary-value problem of diffraction a parallel- or perpendicular-polarized wave from an echelette grating is numerically solved. Parallel and perpendicular Wood's anomalies are investigated. A very strong anomaly for negative incident angle into back-scattering order found.
The MHD activity giving rise to the beta - and density limit in ASDEX Upgrade is analyzed. A detailed description of phenomena occuring prior during disruptions given. characteristics different ELM types occurring are described.
Charge-dependent convective impurity transport is observed in the central core of PBX H-mode discharges by measurement radial profiles for both low- and high-Z intrinsic impurities presence strong sawtooth activity. The time-evolving ${Z}_{\mathrm{eff}}$ profile metallic densities are modeled to yield a diffuison coefficient Z-dependent inward pinch which general agreement with estimates neoclassical plasma region.
TSTR (Tokamak Fusion Test Reactor) has operated since December 1982 with ohmically heated plasmas. Routine operation feedback control of plasma current, position and density been obtained for plasmas Ip≃800 kA, a = 68 cm, R 250 Bt=27 kG. A maximum current 1 MA was achieved q≃2.5. Energy confinement times ~150 msec were measured hydrogen deuterium e 2 x 1013 cm-3, Te(0) 2≃1.5 keV, Ti(0) 1.5 keV Zeff≃1 3. The preliminary results suqgest size-cubed scaling from PLT, are consistent Alcator C...
Spectra of heliumlike nickel, Ni xxvii, have been observed from Tokamak Fusion Test Reactor (TFTR) plasmas with a high-resolution crystal spectrometer. The experimental arrangement permits simultaneous observation the resonance line, intercombination and forbidden lines, all associated satellites due to transitions 1${s}^{2}$nl-1s2l'nl'' n\ensuremath{\ge}2. Relative wavelengths line intensities can thus be determined very accurately. spectral data are in good agreement results present...