Theory of Plasma-Heating by Low-Frequency Waves - Magnetic Pumping and Alfven Resonance Heating

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Bridging the gap to next-step devices – while saving valuable time and resources – requires more than semi-empirical models, which struggle to predict plasma behavior in unexplored parameter regimes. Instead, validated simulation tools are essential, leveraging high-fidelity exascale computing and multi-fidelity models, including AI-based surrogates. To address these challenges, the “EUROfusion Theory and Advanced Simulation Coordination (E-TASC)” initiative was launched in 2021. It includes 15 TSVV (Theory

The recent decision by ITER to move from a Be to a W first wall has significant implications for material transport and deposition, and can be expected to lead to increased W layer growth rate in deposition regions, which may flake leading to plasma disruption. In this work a novel sputtering set-up was implemented in the Magnum-PSI linear plasma device to create W layers under ITER relevant conditions. A W plate was inserted into the plasma edge and biased to cause sputtering of W in an Ar plasma. This spu

Numerical studies of phase transitions in statistical and quantum lattice models provide crucial insights into the corresponding Conformal Field Theories (CFTs). In higher dimensions, comparing finite-volume numerical results to infinite-volume CFT data is facilitated by choosing the sphere S^{d-1} as the spatial manifold. Recently, the fuzzy sphere regulator [Zhu et al, Phys. Rev. X 13, 021009 (2023)] has enabled such studies with exact rotational invariance, yielding impressive agreement with known 3D Isi

This paper focuses on the design and application of low power and low-frequency localization system using received signal strength indication (RSSI). The receiver will wake up from sleeping mode by a modulated magnetic field emitted from a transmitter module. Then it will send messages containing the Received Signal Strength Indication (RSSI) via WiFi with Message Quest Telemetry Transport (MQTT) protocol to an MQTT broker. Using the magnetic coupling effect and RSSI ranging, the system is a unique candidat

Simulating the most external plasma region of a tokamak, the scrape-off layer (SOL), is of crucial importance on the path towards a fusion reactor as heat load on the vessel wall, impurity generation, and overall plasma confinement all depend on the plasma dynamics in this region. The GBS code has been developed to solve the drift-reduced Braginskii equations which describe turbulent behaviour of the plasma in the SOL. Until recently, only limited scenarios were considered in GBS and it was not possible to

Optimization of the plasma discharge can be defined as determination of an optimal time evolution of the plasma parameters to lead a plasma to a desired state keeping it within the specific limits: physical ones (like the Greenwald density limit, low normalized beta and internal inductance values) and technical ones (like the vertical stability limit). The parameters, time-trajectories of which have to be optimized, are the ones significantly changing the plasma state, and, depending on the optimization goa

Simulating the most external plasma region of a tokamak, the scrape-off layer (SOL), is of crucial importance in the way toward a fusion reactor as heat load on the vessel wall, impurity generation, overall plasma confinement, all depend on the plasma dynamics in this region. In the last few years a numerical code, GBS, has been developed for solving the drift-reduced Braginskii equations (DRBE), which describe turbulence in the tokamak SOL. In the present work, we re-formulate the DRBE in a general form th

Earthing of electrical installations is mainly governed by safety rules. Electromagnetic compatibility also deals with earthing, among other circuit characteristics. Tokamaks are large-scale electrical installations that are known to generate large and low frequency magnetic fields as well as large and high frequency electric fields. Four European Tokamak installations have been investigated, from the earthing point of view, to identify appropriate techniques to earth the electrical equipment and to provide

The development of new technologies to monitor drugs concentration directly in patient’s blood is absolutely required to succeed in personalized drug therapies. In this study, Etoposide - a well-known anti-cancer drug - has been chosen as model for cyclic voltammetry detection of drugs. Carbon nanotubes are chosen as electron-transfer mediators to enhance the system sensitivity. A very low frequency and low slope triangular-wave potential is required to acquire cyclic voltammograms. Cyclic voltammograms are

Low frequency background noise in rooms generated by numbers of human activities - traf-fic, railway, airport and industrial noise - creates major disturbances from loss of speech in-telligibility to stress and fatigue. To overcome such situations classical solutions generally consist in deploying resonator-like absorbing materials to reduce both the acoustic level and the reverberation time. Unfortunately these traditional acoustic treatments are not efficient enough to attain A-weighted level specificatio

Experiments are conducted on JET to assess the potential for plasma diagnostic spectroscopy and mode stability control, of Alfven eigenmodes (AEs), excited by external antennas and by energetic particles. Information on the time evolution of the nonmonotonic current profile in advanced scenarios can be obtained from the frequency and mode number. of AEs driven by energetic particles. The appearance of a rational surface associated with a minimum value in the safety factor profile can be inferred with a time

In current tokamaks and, in particular, in future larger devices such as ITER, the control of neo-classical tearing modes (NTM) is essential for achieving high performance in terms of the beta limit. A commonly used scheme for NTM stabilization consists in driving a helical current at the resonance surface of interest with electron-cyclotron-current-drive. Depending on the ratio between the magnetic island size and the RF beam width, complete stabilization of the NTM will only be achieved with deep RF power

*This book provides a full, general purpose and application independent exposition of the moiré phenomenon. * Based on the Fourier theory it leads the reader through the various phenomena which occur in the superposition of repetitive layers, both in the image and in the spectral domains. * The first chapters of the book present the basic theory which covers the superposition of monochrome, periodic layers. In later chapters the theory is extended to the even more interesting cases of polychromatic moirés a

Confinement in TCV electron cyclotron heated discharges was studied as a function of plasma shape, i.e. as a function of elongation, 1.1 < kappa < 2.15, and triangularity, -0.65 less than or equal to delta less than or equal to 0.55. The electron energy confinement time was found to increase with elongation, owing in part to the increase of plasma current with elongation. The beneficial effect of negative triangularities was most effective at low power and tended to decrease at the higher powers used. The l

A high-order, multivariable, modern plasma controller has been designed using H-infinity optimal control techniques and tested oil the Tokamak Configuration Variable (TCV) tokamak. An initial design for the control of the plasma current, position, and shape parameters is described. The design process was based on the CREATE-L linearized model of TCV, and the controller was implemented oil a digital processor. The results demonstrated that the required performance was delivered and the controller response wa

The maximum normalized beta achieved in long-pulse tokamak discharges at low collisionality falls significantly below both that observed in short pulse discharges and that predicted by the ideal MHD theory. Recent long-pulse experiments, in particular those simulating the International Thermonuclear Experimental Reactor (ITER) [M. Rosenbluth et al., Plasma Physics and Controlled Nuclear Fusion (International Atomic Energy Agency, Vienna, 1995), Vol. 2, p. 517] scenarios with low collisionality nu(e)*, are o

Kinetic theory is used to develop equations describing dynamics of small-amplitude electromagnetic perturbations in toroidal axisymmetric plasmas. The closed Vlasov-Maxwell equations are first solved for a hot stationary plasma using the expansion in the small parameter epsilon(e) = rho/L, where rho is the Larmor radius and L a characteristic length scale of the stationary state. The ordering and additional assumptions are specified so as to obtain the well-known Grad-Shafranov equation. The dielectric tens

Poloidal asymmetries in the electron density profiles and limiter diagnostics suggest that poloidal and toroidal flows exist in the SOL and edge plasma of the TEXTOR tokamak. A fast reciprocating probe located at the outer midplane provides profiles of the basic plasma parameters including radial electric field and fluctuation driven transport. Based on the probe measurements, we calculate the E(r) X B(t) drift velocities and phase velocities of the turbulence. The measurements are compared to each other. T

Theory of Plasma-Heating by Low-Frequency Waves - Magnetic Pumping and Alfven Resonance Heating

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Towards Digital Twins of Fusion Systems

Growth, Characterization and Adhesion of Thick Deposited Tungsten Layers Under Transient Loading in Magnum-PSI

Exact diagonalization, matrix product states and conformal perturbation theory study of a 3D Ising fuzzy sphere model

Application of a Low Frequency, Low Power Radio Frequency Positioning System for Real Time Indoor Positioning

Implementation of Diverted Equilibria in the GBS simulation code

Numerical optimization of ramp-down phases for TCV and AUG plasmas

A flexible numerical scheme for simulating plasma turbulence in the tokamak scrape-off layer

ITER-Earthing

Nano-Sensor and Circuit Design for Anti-Cancer Drug Detection

Active low-frequency modal noise cancellation for room acoustics: an experimental study

Diagnosis and study of Alfven eigenmodes stability in JET (invited)

Power modulation capabilities of the 140 GHz/1 MW gyrotron for the stellarator Wendelstein 7-X

The theory of the moiré phenomenon

Energy confinement and MHD activity in shaped TCV plasmas with localized electron cyclotron heating

A modern plasma controller tested on the TCV tokamak

Beta limits in long-pulse tokamak discharges

Dielectric Tensor Operator of Hot Plasmas in Toroidal Axisymmetrical Systems

Flows in the Textor Sol and Edge Plasma