Publications associées à Fréquence plasma

Divertor turbulence characterisation using Gas Puff Imaging in the TCV tokamak

The performance of magnetic confinement fusion devices, such as tokamaks, is strongly correlated to the phenomena that occur in the boundary region of the plasma core that faces the wall of the device. The dominant cross-field transport mechanisms from the ...

EPFL2024

Modelling of energetic particle drive and damping effects on TAEs in AUG experiment with ECCD

Alexander Karpushov, Giovanni Tardini

The impact of electron cyclotron current drive (ECCD)-driven current on toroidicity-induced Alfven eigenmodes (TAEs) in experiments on the AUG tokamak is investigated numerically. The dynamical evolution of the plasma profiles and equilibria are modelled w ...

IOP Publishing Ltd2024

Hosing of a Long Relativistic Particle Bunch in Plasma

Ambrogio Fasoli, Ivo Furno, Patrick Blanchard, Yanis Andrebe, Riccardo Agnello, Christine Stollberg, Sun Hee Kim, Alban Sublet, Shuai Liu

Experimental results show that hosing of a long particle bunch in plasma can be induced by wakefields driven by a short, misaligned preceding bunch. Hosing develops in the plane of misalignment, selfmodulation in the perpendicular plane, at frequencies clo ...

Amer Physical Soc2024

Model-based electron density estimation using multiple diagnostics on TCV

Olivier Sauter, Federico Alberto Alfredo Felici, Cristian Galperti

Estimation of the dynamic evolution of the electron plasma density during a tokamak discharge is crucial since it directly affects the plasma performance, confinement and stability. Therefore it needs to be monitored and controlled. Knowledge of the densit ...

ELSEVIER SCIENCE SA2023

Model-based impurity emission front control using deuterium fueling and nitrogen seeding in TCV

Basil Duval, Christian Gabriel Theiler, Cristian Galperti, Artur Perek

This paper presents the first result using nitrogen-seeded exhaust feedback control of the NII impurity emission front in TCV. The NII emission front position is consistently located below its commonly used CIII counterpart, indicating the NII emission fro ...

IOP Publishing Ltd2023

Predictive modeling of Alfvén eigenmode stability in inductive scenarios in JT-60SA

Javier García Hernández, Matteo Vallar, Antonio José Pereira de Figueiredo

The JT-60SA device offers unique conditions before ITER for the study of the interaction of energetic particles with plasma waves. With similar dimensions to JET, e.g., a major radius but with a slightly more elongated plasma volume, JT-60SA is used as a h ...

Frontiers Media Sa2023

Characterization of transversely confined electron beam-generated plasma using two-dimensional particle-in-cell simulations

Haomin Sun, Guang-Yu Sun

Electron beam-generated plasmas (EBPs) have been used to modify the surface properties. In certain applications, EBPs are transversely confined and their properties are of value to the treatment. In this paper, the characteristics of an electron beam-gener ...

American Institute of Physics (AIP)2023

Comparison of momentum transport in matched hydrogen and deuterium H-mode plasmas in ASDEX Upgrade

Basil Duval, Emiliano Fable, Giovanni Tardini

Advanced momentum transport analysis is used to study matched hydrogen (H) and deuterium (D) plasmas in the core of ASDEX Upgrade. The aim is to validate gyrokinetic theory and assess a possible isotope dependence. The methodology extracts momentum diffusi ...

IOP Publishing Ltd2023

Locked mode detection during error field identification studies

Olivier Sauter

At the beginning of a machine operation, an assessment of the intrinsic error fields, spurious magnetic field perturbations which can affect plasma dynamics, is often carried out by executing the compass scan method [Scoville J.T. et al. Nucl. Fusion 43 25 ...

ELSEVIER SCIENCE SA2023

The competing effects of wave amplitude and collisions on multi-ion species suppression of stimulated Brillouin scattering in inertial confinement fusion Hohlraums

Stephan Brunner

Reduction in stimulated Brillouin scattering (SBS) from National Ignition Facility Hohlraums has been predicted through the use of multi-ion species materials on Hohlraum walls. This approach to controlling SBS is based upon introducing a lighter ion speci ...

2023

Maximum likelihood bolometry for ASDEX upgrade experiments

Olivier Claude Martin Février, Riccardo Rossi

Bolometry is an essential diagnostic for calculating the power balances and for the understanding of different physical aspects of tokamak experiments. The reconstruction method based on the Maximum Likelihood (ML) principle, developed initially for JET, h ...

Iop Publishing Ltd2023

Development of the self-modulation instability of a relativistic proton bunch in plasma

Ambrogio Fasoli, Ivo Furno, Patrick Blanchard, Yanis Andrebe, Riccardo Agnello, Christine Stollberg, Sun Hee Kim, Ana Francisca Leal Silva Soares, Alban Sublet, Samuel Rey-Mermet, Shuai Liu

Self-modulation is a beam-plasma instability that is useful to drive large-amplitude wakefields with bunches much longer than the plasma skin depth. We present experimental results showing that, when increasing the ratio between the initial transverse size ...

2023

Global 'zero particle flux-driven' gyrokinetic analysis of the density profile for a TCV plasma

Olivier Sauter, Stephan Brunner, Gabriele Merlo, Alberto Mariani

The tokamak `a configuration variable (TCV) is a small-sized tokamak, where finite size effects (often called 'rho-star' or 'global' effects) could significantly impact the heat and particle fluxes, leading to discrepancies between gyrokinetic flux-tube re ...

IOP Publishing Ltd2023

Performance assessment of a tightly baffled, long-legged divertor configuration in TCV with SOLPS-ITER

Basil Duval, Holger Reimerdes, Christian Gabriel Theiler, Guang-Yu Sun, Olivier Claude Martin Février, Claudia Colandrea

Numerical simulations explore a possible tightly baffled, long-legged divertor (TBLLD) concept in a future upgrade of the tokamak à configuration variable (TCV). The SOLPS-ITER code package is used to compare the exhaust performance of several TBLLD config ...

IOP Publishing Ltd2023

Comparison of JET-C DD neutron rates independently predicted by the ASCOT and TRANSP Monte Carlo heating codes

Henri Weisen

Simulations of the DD neutron rates predicted by the ASCOT and TRANSP Monte Carlo heating codes for a diverse set of JET-C (JET with carbon plasma facing components) plasmas are compared. A previous study (Weisen et al 2017 Nucl. Fusion 57 076029) of this ...

IOP Publishing Ltd2022

Modelling of sawtooth-induced fast ion transport in positive and negative triangularity in TCV

Olivier Sauter, Basil Duval, Alexander Karpushov, Duccio Testa, Mario Ludovico Podesta, Antoine Pierre Emmanuel Alexis Merle, Marcelo Baquero Ruiz, Dmytry Mykytchuk, Matteo Vallar, Lorenzo Stipani

Internal kinks are a common magneto hydro-dynamic (MHD) instability observed in tokamak operation when the q profile in the plasma core is close to unity. This MHD instability impacts both the transport of the bulk plasma (current, particle and energy tran ...

IOP Publishing Ltd2022

Upgrade of the neutral beam heating system on the TCV tokamak - second high energy neutral beam

Ambrogio Fasoli, Basil Duval, Stefano Coda, Yves Martin, Holger Reimerdes, Alexander Karpushov, Damien Fasel, Umar Sheikh, Matthieu Toussaint, Pierre Lavanchy, Ugo Siravo, Rémy Jacquier, Marcelo Baquero Ruiz, Frédéric Dolizy, Jérémie Dubray, Dmytry Mykytchuk, Jesús Poley Sanjuán, Blaise Marlétaz, Matteo Vallar, Filippo Bagnato, Lorenzo Martinelli, Claudia Colandrea

The TCV tokamak continues to leverage its unique shaping capabilities, flexible heating systems and modern control system to provide a stepladder approach for extrapolations of experimental results from different ma-chines to ITER and DEMO. TCV's configura ...

ELSEVIER SCIENCE SA2022

Helicon wave plasma generated by a resonant birdcage antenna: magnetic field measurements and analysis in the RAID linear device

Ivo Furno, Alan Howling, Philippe Frédérique Bruno Guittienne, Rémy Jacquier, Riccardo Agnello

This paper describes a helicon-wave-sustained plasma generated by a novel birdcage antenna with cosine azimuthal current distribution. The resonant birdcage source maintains a stable intense plasma column from low (300 W) to high (10 kW) steady-state RF po ...

2021

The operational space for divertor power exhaust in DEMO with a super-X divertor

Holger Reimerdes, Marco Wischmeier, Mirko Wensing

SOLPS-ITER simulations of the European DEMO reactor with a Super-X divertor, which has larger major radius at the outer target and increased connection length, show an increased operational space for divertor power exhaust compared to the conventional sing ...

IOP Publishing Ltd2021

Rapid optimization of stationary tokamak plasmas in RAPTOR: demonstration for the ITER hybrid scenario with neural network surrogate transport model QLKNN

Olivier Sauter, Federico Alberto Alfredo Felici, Michele Marin, Simon Van Mulders

This work presents a fast and robust method for optimizing the stationary radial distribution of temperature, density and parallel current density in a tokamak plasma and its application to first-principle-based modeling of the ITER hybrid scenario. A new ...

IOP Publishing Ltd2021