Christian Gabriel Theiler

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Fusion plasma regimes with a strongly radiating magnetic 𝑋 point are promising candidates to tackle the outstanding power exhaust challenge in reactor-scale devices. In this Letter, we report on a new type of 𝑋-point radiator, the XPTR (𝑋-point target radi ...

The most efficient and promising operational regime for the International Thermonuclear Experimental Reactor tokamak is the high-confinement mode. In this regime, however, periodic relaxations of the plasma edge can occur. These edge-localized modes pose a ...

We present simultaneous profiles of the poloidal distribution of electron temperature and density (Te, ne), the poloidal emissivity distributions of a range of spectral lines together with the corresponding ion temperatures, Ti, in the TCV divertor plasma. ...

A new gas puff imaging diagnostic has been installed on the TCV tokamak, providing two-dimensional insights into scrape-off-layer (SOL) turbulence dynamics above, at and below the magnetic X-point. A detailed study in L-mode, attached, lower single-null di ...

The Super-X Divertor (SXD) is an alternative divertor configuration leveraging total flux expansion at the Outer Strike Point (OSP). While the extended 2-Point Model (2PM) predicts facilitated detachment access and control in the SXD configuration, these a ...

In inboard-limited plasmas, the Scrape-Oﬀ Layer (SOL) shows two regions: the near SOL, extending a few mm from the Last Closed Flux Surface (LCFS), characterized by a steep gradient of the parallel heat ﬂux radial proﬁle, and a far SOL, typically some cm w ...

In simple magnetized toroidal plasmas, field-aligned blobs originate from ideal interchange waves and propagate radially outward under the effect of

\grad B

and curvature induced

E \times B

drifts. We report on the first experimental two-dimensional me ...

We present the design and operation of a suite of Gas Puff Imaging (GPI) diagnostic systems installed on the Tokamak a Configuration Variable (TCV) for the study of turbulence in the plasma edge and Scrape-Off-Layer (SOL). These systems provide the unique ...

Divertor detachment is investigated on the Tokamak a Configuration Variable (TCV) for conventional and alternative double-null (DN) magnetic geometries in L-mode, Ohmic density ramps and then compared to precisely matched single-null (SN) geometries. The p ...

In this work we provide experimental insights into the impact of plasma-molecule interactions on the target ion flux decrease during divertor detachment achieved through a core density ramp in the TCV tokamak. Our improved analysis of the hydrogen Balmer s ...

The Thermal Helium Beam (THB) is a diagnostic for simultaneously measuring the electron temperature and density profiles of the plasma edge and scrape off layer (SOL). It exploits the line ratio technique of selected He line intensities, emitted by He gas ...

Future fusion reactors require a safe, steady-state divertor operation. With deep divertor detachment, which is typically induced by impurity seeding, the radiation concentrates in a small region at the X-point or on closed flux surfaces above the X-point. ...

Power exhaust is a crucial issue for future fusion reactors. Divertor detachment and the required power dissipation fractions of about 95% are foreseen to be achieved by impurity seeding. In a tokamak, at high seeding levels the radiation often concentrate ...

A simple analytic model for the repartition of the Scrape-Off Layer (SOL) exhaust power between the inner and outer divertors in a diverted low-density tokamak plasma is introduced. Electron heat conduction is assumed to dominate the heat transport, from t ...

This paper presents a quantitative validation of Scrape-Off Layer Plasma Simulation-ITER (SOLPS-ITER) simulations against the TCV-X21 reference case and provides insights into the neutral dynamics and ionization source distribution in this scenario. TCV-X2 ...

In this paper, we present the first results of a systematically designed multi-input multi-output gas-injection controller on Tokamak a Configuration Variable (TCV). We demonstrate the simultaneous real-time control of the NII emission front position and l ...

Three-dimensional and two-dimensional seeded blob simulations are performed with five different fluid models, all based on the drift-reduced Braginskii equations, and the numerical results are compared among themselves and validated against experimental me ...

Recent TCV experiments confirm the predicted formation of an electric potential well, below the magnetic X-point, in configurations with unfavorable

B_t

field direction (ion

\nabla B

drift away from the divertor), that substantially reshapes the typica ...

Electrostatic turbulence, related structures and their effect on particle, heat and toroidal momentum transport are investigated in TORPEX simple magnetized plasmas using high-resolution diagnostics, control parameters, linear fluid models and nonlinear nu ...

The ion temperature is not frequently measured in the boundary of magnetic fusion devices. Comparisons among different ion temperature techniques and simulations are even rarer. Here we present a comparison of ion temperature measurements in the boundary o ...

Christian Gabriel Theiler

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𝑋-Point Target Radiator Regime in Tokamak Divertor Plasmas

Effect of energetic ions on edge-localized modes in tokamak plasmas

Interpretation of divertor ion temperature measurements from an attached towards a detached regime

X-point and divertor filament dynamics from gas puff imaging on TCV

Parallel flows as a key component to interpret Super-X divertor experiments

Understanding and suppressing the near Scrape-Oﬀ Layer heat flux feature in inboard-limited plasmas in TCV

Direct two-dimensional measurements of the eld-aligned current associated with plasma blobs

Gas puff imaging on the TCV tokamak

Detachment in conventional and advanced double-null plasmas in TCV

A study of the influence of plasma-molecule interactions on particle balance during detachment

Role of radiation re-absorption in the thermal helium beam diagnostic

The X-Point radiating regime at ASDEX Upgrade and TCV

X-point radiation: From discovery to potential application in a future reactor

Conduction-based model of the Scrape-Off Layer power sharing between inner and outer divertor in diverted low-density tokamak plasmas

Validation of SOLPS-ITER simulations against the TCV-X21 reference case

Systematic design of a multi-input multi-output controller by model-based decoupling: a demonstration on TCV using multi-species gas injection

Blob dynamics in the TORPEX experiment: a multi-code validation

Experimental verification of X-point potential well formation in unfavorable magnetic field direction

Electrostatic instabilities, turbulence and fast ion interactions in the TORPEX device

An assessment of ion temperature measurements in the boundary of the Alcator C-Mod tokamak and implications for ion fluid heat flux limiters