Publications by Olivier Sauter

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

Selected set of samples from JET ITER-Like Wall (JET-ILW) divertor tiles exposed in 2015-2016 has been analysed using Thermal Desorption Spectrometry (TDS). The deuterium (D) amounts obtained with TDS were compared with Nuclear Reaction Analysis (NRA). The ...

Experiments, gyrokinetic simulations and transport predictions were performed to investigate if a negative triangularity (NT) L-mode option for the Divertor Tokamak Test (DTT) full-power scenario would perform similarly to the positive triangularity (PT) H ...

Progress in the area of MHD stability and disruptions, since the publication of the 1999 ITER Physics Basis document (1999 Nucl. Fusion 39 2137-2664), is reviewed. Recent theoretical and experimental research has made important advances in both understandi ...

The Advanced Tokamak scenario, one of the modes of operation being considered for ITER, relies on the attainment of a high bootstrap current fraction. This scenario is typically characterized by an internal transport barrier (ITB). An internal feedback loop then governs the current profile, which strongly affects the confinement and thus the properties and location of the high-gradient region, where in turn the bootstrap current component is localized. The bootstrap current fraction can reach 100% only if t

The objective of thermonuclear fusion consists of producing electricity from the coalescence of light nuclei in high temperature plasmas. The most promising route to fusion envisages the confinement of such plasmas with magnetic fields, whose most studied ...

Beryllium limiter marker tiles were exposed to plasma in the Joint European Torus to diagnose the erosion of main chamber wall materials. A limiter marker tile consists of a beryllium coating layer (7-9 mu m) on the top of bulk beryllium, with a nickel int ...

The mutual interactions of ion temperature gradient (ITG) driven modes, zonal flows and geodesic acoustic modes (GAM) in tokamak plasmas are investigated using a global nonlinear gyrokinetic formulation with totally unconstrained evolution of temperature g ...

Plasma shape control is a fundamental tool for effective tokamak operation, allowing improved plasma performance and the pursuit of challenging scientific objectives. In this framework, the Tokamak á Configuration Variable (TCV) of the École Polytechnique ...

The Alfvén instability nonlinearly excited the energetic-particle-driven geodesic acoustic mode on the ASDEX-Upgrade tokamak, as demonstrated experimentally. The mechanism of the energetic-particle-driven geodesic acoustic mode excitation and the mode nonl ...

Recent experiments in the Joint European Torus (JET) have provided evidence of sawtooth stabilization by fast ions arising from deuterium neutral beam injection (NBI). A possible theoretical basis for the interpretation of the observed sawtooth period behaviour is investigated and predictions are compared with experimental results, using a sawtooth period model developed to predict the sawtooth period in the International Thermonuclear Experimental Reactor (ITER). Unlike the case of ion cyclotron resonance

Tokamaks are experimental nuclear fusion reactors that exploit magnetic-field-generating coils to confine a plasma. In these devices, plasma shape control is crucial to achieving high performance and pursuing challenging scientific objectives. With its lar ...

The high confinement regime (H-mode) is considered fundamental for high-performance operation in next-step tokamaks. It is generally characterized by the occurrence of edge localized modes (ELMs), even though several no-ELM and small-ELM regimes have extended their operational space in the past years (Viezzer et al 2023 Nucl. Mater. Energy 34 101308). The control and suppression of these modes is a priority for the development of scenarios with a confinements good enough for the ITER baseline (Sips et al 20

The European Integrated Tokamak Modelling Task Force (ITM-TF) is developing a new type of fully modular and flexible integrated tokamak simulator, which will allow a large variety of simulation types. This ambitious goal requires new concepts of data struc ...

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

Neutron emission spectroscopy is a diagnostic technique that allows for energy measurements of neutrons born in nuclear reactions. The JET tokamak fusion experiment (Culham, UK) has a special role in this respect as advanced spectrometers for 2.5 MeV and 1 ...

Maximizing fusion performance in tokamaks relies on high energy confinement, often achieved through distinct operating regimes. The automated labeling of these confinement states is crucial to enable large-scale analyses or for real-time control applicatio ...

Bayesian integrated data analysis combines measurements from different diagnostics to jointly measure plasma parameters of interest such as temperatures, densities, and drift velocities. Integrated data analysis of fast-ion measurements has long been hampe ...

Deposition of electron cyclotron waves at high-power densities for heating and current drive in a tokamak plasma generates a population of fast electrons and therefore the velocity distribution of the electron population will deviate from a Maxwellian. Apa ...

Electrostatic microinstabilities in ion internal barrier (ITB) and H-mode discharges of the ASDEX Upgrade tokamak [O. Gruber, R. Arslanbekov, C. Atanasiu , Nucl. Fusion 41, 1369 (2001)] have been investigated with a full radius gyrokinetic code. The code models linear stability and includes the effect of an equilibrium radial electric field and trapped electrons. In order to simulate plasmas in experimental conditions [k(perpendicular to)rho(L)similar toO(1)], the long wavelength approximation in the quasin

In this chapter, we review the progress in MHD stability, disruptions and control in magnetic fusion research that has occurred over the past (more than) one and a half decades since the publication by Hender et al in 2007 on the same topic as part of the update of ITER Physics Basis. During this period, remarkable progress has been achieved in the understanding of the basic physics and overall control of MHD instabilities through a wide spectrum of dedicated experiments, theory and modeling. The sawtooth a

Olivier Sauter

Chat with Graph Search

Investigation of deuterium trapping and release in the JET divertor during the third ILW campaign using TDS

Negative triangularity scenarios: from TCV and AUG experiments to DTT predictions

Chapter 3: MHD stability, operational limits and disruptions

Full Bootstrap Discharge Sustainment in Steady State in the TCV Tokamak

A control oriented strategy of disruption prediction to avoid the configuration collapse of tokamak reactors

Micro ion beam analysis for the erosion of beryllium marker tiles in a tokamak limiter

Effects of plasma current on nonlinear interactions of ITG turbulence, zonal flows and geodesic acoustic modes

Design and implementation of a model-based hierarchical architecture for plasma shape control in the TCV tokamak

Nonlinear excitation of energetic particle driven geodesic acoustic mode by resonance overlap with Alfvén instability in ASDEX Upgrade

Neutral beam stabilization of sawtooth oscillations in JET

Design of a novel plasma shape controller for the TCV tokamak

Experimental characterization of inter-ELM modes in type-I ELMy scenarios at TCV using the thermal helium beam diagnostic

A generic data structure for integrated modelling of tokamak physics and subsystems

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

Neutron emission spectroscopy of D plasmas at JET with a compact liquid scintillating neutron spectrometer

Robust Confinement State Classification with Uncertainty Quantification Through Ensembled Data-driven Methods

Bayesian Integrated Data Analysis of Fast-Ion Measurements by Velocity-Space Tomography

Influence of non-Maxwellian velocity distributions during ECRH and ECCD on electron temperature measurements by Thomson scattering

Simulations of global electrostatic microinstabilities in ASDEX Upgrade discharges

MHD, disruptions and control physics: Chapter 4 of the special issue: on the path to tokamak burning plasma operation