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Machine-scale instabilities in fusion devices are commonly described using magnetohydrodynamics (MHD), however kinetic effects can significantly affect MHD instabilities through kinetic compression and wave-particle interaction. We propose a new code that solves the drift-kinetic-MHD equations using a spectral method, formulated using a Case-Van Kampen approach (N. G. Van Kampen, Physica 21 , 949 (1955)). The eigenvectors of the standardised eigenvalue problem are composed of the perpendicular MHD-like disp

Benign termination, in which magnetohydrodynamic (MHD) instabilities deconfine runaway electrons (REs) following hydrogenic injections, is a promising strategy for mitigating dangerous RE loads after disruptions. Recent experiments on the Joint European Torus (JET) have explored this scenario at higher pre-disruptive plasma currents than are achievable on other devices, revealing challenges in obtaining benign terminations at I p ≥ 2.5 MA. This work analyzes the evolution of these high-current RE beams and

Accurate and rapid simulation of the free boundary tokamak plasma equilibrium evolution is essential for modern plasma control, stability analysis, and scenario development. This paper presents the Free-Boundary Grad-Shafranov Evolutive (FGE) code, a highly flexible and control-oriented solver designed to address the challenges posed by advanced plasma configurations across a range of devices. FGE evolved from the FBT [Hofmann, 1988] and LIUQE [Moret et al., 2015] codes and is part of the MEQ suite, sharing

Mixed monolayer doping (MMLD) is an attractive strategy for controllable low‐dose, low‐energy silicon doping via surface chemistry, yet the influence of carbon removal and surface effects on electronic properties remains unclear. In this work, silicon is doped using mixed monolayers of allyldiphenylphosphine (ADP) and 1‐undecene, followed by O 2 plasma ashing, SiO 2 capping, and rapid thermal annealing (RTA). The plasma treatment is systematically investigated, identifying conditions that effectively remove

Upward lightning occurs generally from tall structures. The mechanism of the initiation of upward lightning is not yet fully understood. Upward lightning can be classified into two categories based on either the absence or the presence of other lightning a ...

This paper presents a survey of the experiments on runaway electrons (RE) carried out recently in frames of EUROFusion Consortium in different tokamaks: COMPASS, ASDEX-Upgrade, TCV and JET. Massive gas injection (MGI) has been used in different scenarios f ...

The potential of the hybrid scenario (first developed as an advanced inductive scenario for high fluence) as a regime for high-beta, steady-state plasmas is demonstrated on the DIII-D tokamak. These experiments show that the beneficial characteristics of h ...

The phenomenon of resistive switching is based on nanoscale changes in the electrical properties of the interface. In the present study, conductive atomic force microscope based nanoscale measurements of copper oxide (CuO)-multilayer graphene (MLG) hybrid interface based devices have been carried out to understand changes in the electrical properties during resistive switching of the Ti–CuO/MLG-Cu memory cells having different dimensions fabricated on the same substrate using stencil lithography technique.

TCV is acquiring a new 1 MW neutral beam and 2 MW additional third-harmonic electron cyclotron resonance heating (ECRH) to expand its operational range. Its existing shaping and ECRH launching versatility was amply exploited in an eclectic 2013 campaign. A ...

The Tokamak a Configuration Variable, TCV, has used Electron Cyclotron Heating and Current Drive as its only auxiliary heating system for nearly two decades. In addition to basic plasma heating and current profiling, ECH and ECCD under either feedforward o ...

Winsor et al. [1] first derived the geodesic acoustic mode (GAM) to be an elec-trostatic perturbation, localized within a narrow radial region of the plasma. There is, however, recent experimental evidence that the GAM also has a magnetic component with poloidal mode number 𝑚 = 2, existing outside the GAM surface, and even outside the plasma. Such a signal in 𝛿𝐵𝜃, with angular dependence sin2𝜃, has been detected in JT-60U [2] and in TCV [3] (possibly in other machines

The ITER plasma control system (PCS) will play a central role in enabling the experimental program to attempt to sustain DT plasmas with Q = 10 for several hundred seconds and also support research toward the development of steady-state operation in ITER. ...

Transport analyses using first-principle turbulence codes and 11/2-D transport codes usually study radial transport properties between the tokamak plasma magnetic axis and a normalized minor radius around 0.8. In this region, heat transport shows significa ...

Dealing with electromagnetic fields, in particular current and related magnetic fields, yields "natural" physical vector relations in 3-D. However, when it comes to choosing local coordinate systems, the "usual" right-handed systems are not necessarily the ...

The primary goal of hybrid scenarios in tokamaks is to enable high performance operation with large plasma currents whilst avoiding MHD instabilities. However, if a local minimum in the safety factor is allowed to approach unity, the energy required to ove ...

Turbulence in the scrape-off-layer (SOL) of magnetic fusion devices is one of the most outstanding issues in magnetic fusion. This open fied lines region determines the boundary condition of the core plasma and controls the plasma refueling, heat losses and impurity dynamics, therefore governing the fusion power output of the entire device. In this work, we present the global fluid code GBS [Ricci et al., Plasma Phys. Control. Fusion 54, 124047, 2012]. It employs a 5 field drift-reduced Braginskii model for

In the simple magnetized torus TORPEX, field-aligned blobs originate from ideal interchange waves and propagate radially outward due to del B and curvature induced drifts. Time-resolved two-dimensional measurements of the field-aligned current density J(pa ...

High-confinement mode (H-mode) is a promising reference scenario for ITER. But we are still facing major issues because of instabilities. They expel periodically some of the energy, which can damage the device. These instabilities are called the edge localized modes (ELM) and are not yet fully theoretically understood. The present work is a study on the profiles evolution in between ELMs and on the ELM effects. This may help to have a better understanding of the conditions before the ELM. We use the simulat

Information about the poloidal field inside the plasma and about the current density profile is essential for the understanding of the behavior of tokamak plasmas. The poloidal field outside the plasma edge is easily measured by a set of magnetic coils, wh ...

The TCV tokamak has the dual mission of supporting ITER and exploring alternative paths to a fusion reactor. Its most unique tools are a 4.5 MW electron cyclotron resonance heating system with seven real-time controllable launchers and a plasma control system with 16 independent shaping coils. Recent upgrades in temperature, density and rotation diagnostics are being followed by new turbulence and suprathermal electron diagnostics, and a new digital real-time network has been commissioned. The shape control

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Study of kinetic effects on MHD instabilities in cylindrical geometry using a spectral hybrid kinetic-MHD code

Variability of MHD instabilities in benign termination of high-current runaway electron beams in the JET and DIII-D tokamaks

FGE: A Fast Free-Boundary Grad-Shafranov Evolutive Solver

Impact of Plasma Ashing on Mixed Monolayer Doping of Silicon

On the Initiation of Upward Negative Lightning by Nearby Lightning Activity: An Analytical Approach

Comparison of runaway electron generation parameters in small, medium-sized and large tokamaks-A survey of experiments in COMPASS, TCV, ASDEX-Upgrade and JET

High-beta, steady-state hybrid scenario on DIII-D

Exploring Nanoscale Electrical Properties of CuO-Graphene Based Hybrid Interfaced Memory Device by Conductive Atomic Force Microscopy

The Science Program of the TCV Tokamak: Exploring Fusion Reactor and Power Plant Concepts

Selected highlights of ECH/ECCD physics studies in the TCV tokamak

Global structure and magnetic components of geodesic acoustic modes in shaped tokamak plasmas

Physics of the conceptual design of the ITER plasma control system

On the non-stiffness of edge transport in L-mode tokamak plasmas

Tokamak coordinate conventions: COCOS

Magnetohydrodynamic helical structures in nominally axisymmetric low-shear tokamak plasmas

Recent numerical developments in scrape-off-layer global fluid simulations using the GBS code

Blob current structures in TORPEX plasmas: experimental measurements and numerical simulations

Theoretical study of electronic transport in TCV ELMy H-mode

A Far-Infrared Polarimeter Diagnostic for the Measurement of the Poloidal Magnetic Field in the TCV Tokamak

Progress and Scientific Results in the TCV Tokamak