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

Related publications (39)

What can radars tell us about snowfall microphysics? Insights from a Markov chain Monte-Carlo approach

Alexis Berne, Anne-Claire Marie Billault--Roux

Multi-frequency and Doppler spectral radars are valuable tools for retrieving information on the microphysics of precipitation, particularly snowfall. However, estimating microphysical properties from radar measurements is an ill-posed problem, i.e., diffe ...

American Meteorological Society2025

Real-time density profile simulations on ASDEX Upgrade and the impact of the edge boundary condition

Olivier Sauter, Francesco Pastore

The plasma density is a crucial parameter of tokamak discharge as it impacts the fusion power, stability limits, influences detachment onset and impurities transport. The electron density profile shaping affects the deposition location of the external heat ...

Elsevier BV2025

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

Olivier Sauter, Stefano Coda, Federico Alberto Alfredo Felici, Antoine Pierre Emmanuel Alexis Merle, Cristian Galperti, Adriano Mele, Alessandro Tenaglia

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 ...

IOP Publishing2025

Turnstile flux as a measure for chaotic transport in magnetic confinement fusion devices

Ludovic Rais, Joaquim Loizu Cisquella, Christopher Berg Smiet

We analyze a measure for the degree of chaos in the magnetic fields of magnetic confinement fusion reactors by calculating the lobe fluxes of turnstiles - a method developed for characterizing transport into and out of resonance zones in Hamiltonian dynami ...

2025

Helicon normal modes in radially non-uniform plasma column

Ivo Furno, Philippe Frédérique Bruno Guittienne, Rémy Jacquier, Renat Karimov

Helicon discharges are often considered somewhat mysterious, exhibiting experimental behaviors that are challenging to explain, such as abrupt plasma density jumps, hysteresis, and ‘blue core’ formation, among others. A significant part of the difficulty i ...

2025

The quasi-continuous exhaust regime in ASDEX Upgrade and JET

Olivier Sauter, Benoît Labit

The quasi-continuous exhaust (QCE) regime is a type-I ELM-free high confinement regime obtained at high plasma shaping and high separatrix density. A comparison with various ELM-free regimes in the literature is presented together with potential physics mo ...

Elsevier2025

Testing the accuracy and convergence of scattering calculations using Lorentz reciprocity

Olivier Martin, Andrei Kiselev

We present a simple and versatile approach to test the accuracy of scattering calculations. Based on the Lorentz reciprocity relation, this criterion can be used for any scattering object, especially where a reference solution (e.g. from Mie theory) does n ...

Optica Publishing Group2025

Machine learning methods for locked-mode predictions in MAST-U plasmas

Alessandro Pau

In tokamaks, rotating magneto-hydro-dynamic modes frequently decelerate as their amplitude increases. Once a critical threshold in amplitude is reached, these modes stop rotating into a specific toroidal and poloidal position and are commonly named Locked ...

IOP Publishing Ltd2025

Investigating the influence of divertor baffles on nitrogen-seeded detachment in TCV with SOLPS-ITER simulations and TCV experiments

Basil Duval, Holger Reimerdes, Christian Gabriel Theiler, Olivier Claude Martin Février, Guang-Yu Sun, Claudia Colandrea, Sophie Danielle Angelica Gorno, Luke Simons, Massimo Carpita, Elena Tonello, Richard Alexander David Ducker

Plasma edge simulations with the SOLPS-ITER code are performed to study the influence of divertor baffles on nitrogen-seeded detachment in Tokamak & agrave; Configuration Variable (TCV) single-null, L-mode discharges. Scans of nitrogen seeding rate are con ...

IOP Publishing Ltd2025

Scenario optimization for the tokamak ramp-down phase in RAPTOR: A. Analysis and model validation on ASDEX Upgrade

Olivier Sauter, Federico Alberto Alfredo Felici, Anna Teplukhina, Simon Van Mulders, Cassandre Ekta Contré

We discuss how the combination of experimental observations and rapid modeling has enabled to improve understanding of the tokamak ramp-down phase in ASDEX Upgrade. A series of dedicated experiments has been performed, to disentangle the effect of individu ...

Iop Publishing Ltd2024

Experiments and gyrokinetic simulations of TCV plasmas with negative triangularity in view of DTT operations

Olivier Sauter, Stefano Coda, Alberto Mariani, Justin Richard Ball, Matteo Vallar, Filippo Bagnato

Negative triangularity (NT) scenarios in TCV have been compared to positive triangularity (PT) scenarios using the same plasma shapes foreseen for divertor tokamak test tokamak operations. The experiments provided a NT/PT L-mode pair and a PT H-mode with d ...

Iop Publishing Ltd2024

Overview of fast particle experiments in the first MAST Upgrade experimental campaigns

Matteo Vallar

MAST-U is equipped with on-axis and off-axis neutral beam injectors (NBI), and these external sources of super-Alfv & eacute;nic deuterium fast-ions provide opportunities for studying a wide range of phenomena relevant to the physics of alpha-particles in ...

IOP Publishing Ltd2024

Study of impurity C transport and plasma rotation in negative triangularity on the TCV tokamak

Olivier Sauter, Basil Duval, Stefano Coda, Benoît Labit, Laurie Porte, Alexander Karpushov, Antoine Pierre Emmanuel Alexis Merle, Alessandro Pau, Justin Richard Ball, Filippo Bagnato, Dmytry Mykytchuk

Carbon impurity transport is studied in the TCV tokamak using a charge exchange recombination diagnostic. TCVs flexible shaping capabilities were exploited to extend previous impurity transport studies to negative triangularity (delta < 0). A practical way ...

Iop Publishing Ltd2024

Long plasma duration operation analyses with an international multi-machine (tokamaks and stellarators) database

Stefano Coda, Jeffrey Huang

Combined high-fusion performance and long-pulse operation is one of the key integration challenges for fusion energy development in magnetic devices. Addressing these challenges requires an integrated vision of physics and engineering aspects with the purp ...

IOP Publishing Ltd2024

Error field detection and correction studies towards ITER operation

Olivier Sauter

In magnetic fusion devices, error field (EF) sources, spurious magnetic field perturbations, need to be identified and corrected for safe and stable (disruption-free) tokamak operation. Within Work Package Tokamak Exploitation RT04, a series of studies hav ...

IOP Publishing Ltd2024

Scenario optimization for the tokamak ramp-down phase in RAPTOR. Part B: safe termination of DEMO plasmas

Olivier Sauter, Federico Alberto Alfredo Felici, Emiliano Fable, Anna Teplukhina, Simon Van Mulders, Cassandre Ekta Contré

An optimized plasma current ramp-down strategy is critical for safe and fast termination of plasma discharges in a tokamak demonstration fusion reactor (DEMO), both in planned and emergency scenarios, avoiding plasma disruptions and excessive heat loads to ...

Iop Publishing Ltd2024

Nonlinear simulation of plasma turbulence using a gyrokinetic moment-based approach

Antoine Cyril David Hoffmann

Plasma turbulence plays a fundamental role in determining the performances of magnetic confinement fusion devices, such as tokamaks. Advances in computer science, combined with the development of efficient physical models, have significantly improved our u ...

EPFL2024

Re-design of EU DEMO with a low aspect ratio

Xabier Sarasola Martin

The design point that had been chosen for EU DEMO in 2016 is reviewed here and a modification is proposed with a lower aspect ratio. Previously the same aspect ratio, A, was chosen for EU DEMO as in major tokamak experiments including ITER (A = 3.1), and, ...

Elsevier2024

Gyrokinetic turbulence modeling of a high performance scenario in JT-60SA

Stefano Coda, Stephan Brunner, Aylwin Iantchenko

Local gyrokinetic simulations are used to model turbulent transport for the first time in a representative high-performance plasma discharge projected for the new JT-60SA tokamak. The discharge features a double-null separatrix, 41 MW of combined neutral b ...

IOP Publishing Ltd2024

Interpretative 3D MHD modelling of deuterium SPI into a JET H-mode plasma

Umar Sheikh, Haomin Sun, Mengdi Kong, Cristian Sommariva

The pre-thermal quench (pre-TQ) dynamics of a pure deuterium ( D 2 ) shattered pellet injection (SPI) into a 3 MA / 7 MJ JET H-mode plasma is studied via 3D non-linear MHD modelling with the JOREK code. The interpretative modelling captures the overall evo ...

IOP Publishing Ltd2024