Plasma turbulence plays a key role in determining the spatial-temporal evolution of plasmas in astrophysical, geophysical and laboratory contexts. In particular, turbulence on disparate spatial and temporal scales limits the level of confinement achievable in magnetic confinement fusion experiments and therefore limits the viability of sustainable fusion power. MAST-U is a well-equipped...
ECE bursting is a phenomenon in tokamaks where very intense bursts of microwave power are observed at electron cyclotron emission frequencies. The bursts have a narrow frequency width, ~2-4 GHz, and are generally short lived pulses, ~2 µs, but are very intense, sometimes as high as milliwatt level, which is much higher than the thermal ECE level of 100’s of nanowatts. Since a general...
The new Divertor Tokamak Test facility (DTT [1]), aimed to perform studies regarding power exhaust and divertor load and currently under construction, will be provided with a mix of additional heating systems. The Electron Cyclotron Resonance Heating (ECRH) system is foreseen to accomplish several tasks: plasma heating, MHD control and non-inductive current drive (CD) for transformer...
Electron cyclotron heating (ECH) breakdown and burn-through assist has been adopted to make the ITER start-up, which uses a low toroidal electric field of about 0.3 V/m, more robust. Related studies have been carried out on many fusion machines such as DIII-D, JT-60U, JET, Tore Supra and EAST. However, the required ECH power to ensure an effective breakdown assist at ITER is not yet clear....
First measurements of WEST ECEI diagnostic
R. Sabot1, H K. Park2, G. S. Yun3, and WEST team
1, CEA, IRFM, F-13108 Saint-Paul-lez-Durance, France.
2, Ulsan National Institute of Science and Technology, Ulsan, Korea
3, Pohang University of Science and Technology, Pohang, Korea
Electron Cyclotron Emission imaging (ECEI) diagnostic system is a unique tool for visualizing the...
The requirements of a microwave heating and current drive (mm-wave HCD) system applied to a commercial fusion reactor differ significantly from the present-day systems used for magnetic confinement research devices. The latter require versatile systems that can provide a variety of HCD applications to adapt to changing physics objectives when investigating the optimum plasma scenarios for a...
Many future Fusion devices will rely heavily, if not solely, on electron cyclotron (EC) heating
subsystems to provide bulk heating, instability control (neoclassical tearing mode (NTM)
stabilisation), and thermal instability control. Efficient use of the installed heating power
(gyrotrons) requires low-loss transmission of the power over 100s of meters since the mm-wave
sources need to be...
The electron Bernstein wave (EBW) [1] is an electrostatic mode in magnetized plasmas. The EBW has no limitation of electron density on propagation and the power is absorbed at the electron cyclotron resonance layer. The EBW can also drive plasma current because the wavenumber parallel to the magnetic field $k_{\parallel}$ can be large. The mode conversion process is essential to excite the EBW...
Electron cyclotron (EC) radiation in ITER due to high electron temperature and high magnetic field besides its important role in power loss balance [1, 2], will be a source of additional thermal and electromagnetic loads for microwave and optical diagnostics [3]. EC radiation from the plasma dominates over the nominal stray radiation from electron cyclotron resonance heating (ECRH) and current...
The Electron Cyclotron Emission (ECE) diagnostic has the key function of measuring the core electron temperature profile and electron temperature fluctuation, from the intensity of electron cyclotron radiation emitted from the plasma along the major radius. Other roles of this diagnostic include the measurement of plasma energy, radiated power, runaway electron behaviour, edge electron...
The plug-in efficiency of Electron-Cyclotron-Resonance-Heating (ECRH) systems of nuclear fusion facilities is important for the performance of existing devices and will become a vital performance parameter of future facilities that will have installed multiple tens of megawatts of microwave power. Gyrotrons are the sources of any ECRH system. Today, a gyrotron provides 1-2 MW output power at...
The wave kinetic equation [1, 2] has proved a suitable tool to tackle the problem of wave scattering from density fluctuations in fusion plasmas in the high-frequency limit. Its numerical implementation in the Monte Carlo code WKBeam [3] allowed a detailed study of the effects of beam scattering to be expected in ITER [4, 5]. This approach, although more efficient than a direct numerical...
Electron cyclotron (EC) radiation is a powerful tool in fusion devices. Compared to
other heating and current drive methods, millimeter EC waves exhibit a particularly localized resonance and a radially narrow power deposition region. Localized deposition
allows EC radiation to be used for a wide variety of applications, including (but not
limited to) perturbative transport studies, profile...
Abstract of the "Ray tracing calculations for the First Plasma configuration of ITER Electron Cyclotron Heating system" contribution
Status of the ITER ECRH&CD control system development
