Publications by Luke Simons | EPFL Graph Search

An upper pressure limit for low-Z benign termination of runaway electron beams in TCV

Basil Duval, Holger Reimerdes, Stefano Coda, Joan Decker, Umar Sheikh, Claudia Colandrea, Luke Simons

We present a model for the particle balance in the post-disruption runaway electron plateau phase of a tokamak discharge. The model is constructed with the help of, and applied to, experimental data from TCV discharges investigating the so-called 'low-Z be ...

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, Sophie Danielle Angelica Gorno, Claudia Colandrea, Guang-Yu Sun, Luke Simons

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

𝑋-Point Target Radiator Regime in Tokamak Divertor Plasmas

Basil Duval, Holger Reimerdes, Christian Gabriel Theiler, Curdin Tobias Wüthrich, Garance Hélène Salomé Durr-Legoupil-Nicoud, Daniele Hamm, Sophie Danielle Angelica Gorno, Francesco Pastore, Luke Simons, Artur Perek

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 ...

American Physical Society (APS)2025

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

Patrick Blanchard, Basil Duval, Holger Reimerdes, Christian Gabriel Theiler, Olivier Claude Martin Février, Lorenzo Martinelli, Sophie Danielle Angelica Gorno, Claudia Colandrea, Christine Stollberg, Luke Simons, Artur Perek

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. ...

2025

Experimental investigation of the radial structure of energetic particle driven GAM in TCV

Alexander Karpushov, Mario Ludovico Podesta, Duccio Testa, Umar Sheikh, Luke Simons, Jesús Poley Sanjuán

High amplitude energetic particle geodesic acoustic mode (EGAM) oscillations driven by Neutral Beam (NBI) injected in the direction counter to the toroidal plasma current are observed in the TCV tokamak. The modes appear at frequencies close to the geodesi ...

IOP Publishing Ltd2025

Access to an ELM-suppressed X-point radiator regime in TCV snowflake minus configurations

Basil Duval, Holger Reimerdes, Christian Gabriel Theiler, Curdin Tobias Wüthrich, Olivier Claude Martin Février, Daniele Hamm, Sophie Danielle Angelica Gorno, Guang-Yu Sun, Luke Simons, Artur Perek

TCV’s operating regime with an X-point radiator (XPR) has been broadened by changing the magnetic geometry. XPRs have properties that could make them an attractive power exhaust solution for fusion reactors. These include the conversion of a high fraction ...

Elsevier2024

X-point radiator and power exhaust control in configurations with multiple X-points in TCV

Holger Reimerdes, Christian Gabriel Theiler, Federico Alberto Alfredo Felici, Antoine Pierre Emmanuel Alexis Merle, Curdin Tobias Wüthrich, Olivier Claude Martin Février, Garance Hélène Salomé Durr-Legoupil-Nicoud, Filippo Bagnato, Lorenzo Martinelli, Sophie Danielle Angelica Gorno, Claudia Colandrea, Guang-Yu Sun, Luke Simons, Artur Perek

Novel power exhaust solutions are being developed to address the challenge of integrating a high performance fusion core plasma with a well-protected divertor, if the single null configuration does not scale to a reactor device. This work aims to elucidate ...

American Institute of Physics (AIP)2024

Experimental research on the TCV tokamak

Patrick Blanchard, Stefano Alberti, Ambrogio Fasoli, Timothy Goodman, Yves Martin, Olivier Sauter, Henri Weisen, Ivo Furno, Holger Reimerdes, Jean-Philippe Hogge, Stefano Coda, Alexander Karpushov, Yanis Andrebe, Duccio Testa, Benoît Labit, Christian Gabriel Theiler, Federico Alberto Alfredo Felici, Jérémy Genoud, Hugo De Oliveira, Antoine Pierre Emmanuel Alexis Merle, Antoine Baillod, Joan Decker, Cedric Kar-Wai Tsui, Pedro Andres Molina Cabrera, Umar Sheikh, Cristian Galperti, Marcelo Baquero Ruiz, Aylwin Iantchenko, Mengdi Kong, Francesco Carpanese, Federico Pesamosca, Olivier Claude Martin Février, Simon Van Mulders, Nicola Offeddu, Garance Hélène Salomé Durr-Legoupil-Nicoud, Maurizio Giacomin, Filippo Bagnato, Davide Galassi, Arsène Stéphane Tema Biwole, Lorenzo Martinelli, , , , , , , , , , , , , , , , , , , , , , , ,

Overview of the EUROfusion Tokamak Exploitation programme in support of ITER and DEMO

Patrick Blanchard, Basil Duval, Timothy Goodman, Jean-Marc Moret, Olivier Sauter, Henri Weisen, Holger Reimerdes, Stefano Coda, Alexander Karpushov, Duccio Testa, Benoît Labit, Christian Gabriel Theiler, Federico Alberto Alfredo Felici, Antoine Pierre Emmanuel Alexis Merle, Joan Decker, Cedric Kar-Wai Tsui, Umar Sheikh, Cristian Galperti, Marcelo Baquero Ruiz, Aylwin Iantchenko, Mengdi Kong, Olivier Claude Martin Février, Paulo Giovane Paschoali Pereira Puglia, Simon Van Mulders, Nicola Offeddu, Garance Hélène Salomé Durr-Legoupil-Nicoud, Filippo Bagnato, Davide Galassi, Lorenzo Martinelli, Jean Arthur Cazabonne, Alessandro Pau, Matteo Vallar, Sophie Danielle Angelica Gorno, Claudia Colandrea, Dmytry Mykytchuk, Gino Marceca, Davide Mancini, Cassandre Ekta Contré, Guang-Yu Sun, , , , , , , , , ,

Expulsion of runaway electrons using ECRH in the TCV tokamak

Basil Duval, Stefano Coda, Laurie Porte, Joan Decker, Umar Sheikh, Cristian Sommariva, Arsène Stéphane Tema Biwole, Jean Arthur Cazabonne, Umesh Kumar, Luke Simons

Runaway electrons (REs) are a concern for tokamak fusion reactors from discharge startup to termination. A sudden localized loss of a multi-megaampere RE beam can inflict severe damage to the first wall. Should a disruption occur, the existence of a RE see ...

IOP Publishing Ltd2024

The effect of plasma shaping on high density H-mode SOL profiles and fluctuations in TCV

Holger Reimerdes, Benoît Labit, Christian Gabriel Theiler, Cedric Kar-Wai Tsui, Umar Sheikh, Nicola Vianello, Sophie Danielle Angelica Gorno, Claudia Colandrea, Adriano Stagni, Guang-Yu Sun, Luke Simons, Yi Wang

The impact of plasma shaping on the properties of high density H-mode scrape-off layer (SOL) profiles and transport at the outer midplane has been investigated on Tokamaka configuration variable. The experimental dataset has been acquired by evolving the u ...

IOP Publishing Ltd2024

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

Basil Duval, Holger Reimerdes, Joaquim Loizu Cisquella, Christian Gabriel Theiler, Curdin Tobias Wüthrich, Olivier Claude Martin Février, Garance Hélène Salomé Durr-Legoupil-Nicoud, Davide Galassi, Lorenzo Martinelli, Sophie Danielle Angelica Gorno, Claudia Colandrea, Guang-Yu Sun, Luke Simons, Artur Perek

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 ...

IOP Publishing Ltd2024

Benign termination of runaway electron beams on ASDEX Upgrade and TCV

Basil Duval, Stefano Coda, Joan Decker, Umar Sheikh, Jean Arthur Cazabonne, Claudia Colandrea, Luke Simons, Gergely Papp, Bernhard Sieglin

This paper discusses the development of a benign termination scenario for runaway electron (RE) beams on ASDEX Upgrade and TCV. A systematic study revealed that a low electron density (n e) companion plasma was required to achieve a large MHD instability, ...

Iop Publishing Ltd2024

Power exhaust and core-divertor compatibility of the baffled snowflake divertor in TCV

Basil Duval, Holger Reimerdes, Christian Gabriel Theiler, Umar Sheikh, Olivier Claude Martin Février, Sophie Danielle Angelica Gorno, Claudia Colandrea, Luke Simons

A baffled snowflake minus low-field side (SF-LFS) is geometrically-optimised in tokamak a` configuration variable, increasing divertor neutral pressure, to evaluate the roles of divertor closure (comparing with an unbaffled SF-LFS) and magnetic geometry (c ...

2023

Study of fast-ion-driven toroidal Alfvén eigenmodes impacting on the global confinement in TCV L-mode plasmas

Stephan Brunner, Laurent Villard, Stefano Coda, Javier García Hernández, Aylwin Iantchenko, Justin Richard Ball, Matteo Vallar, Umesh Kumar, Oleg Krutkin, Luke Simons, Jesús Poley Sanjuán, Samuele Mazzi, Baruch Rofman

Following recent observations of unstable Toroidal Alfven Eigenmodes (TAEs) in a counter-current Neutral Beam Injection (NBI) scenario developed in TCV, an in-depth analysis of the impact of such modes on the global confinement and performance is carried o ...

2023

RADCAM-A radiation camera system combining foil bolometers, AXUV diodes, and filtered soft x-ray diodes

Basil Duval, Umar Sheikh, Luke Simons

Measurements of radiated power are critical for characterizing and optimizing tokamak performance. The RADCAM system, comprising arrays of foil bolometers, Absolute eXtreme UltraViolet (AXUV), and filtered soft x-ray diodes, has been constructed to provide ...

2022