Publications by Alexander Karpushov

First Microsecond Velocity-space Resolved Simultaneous Measurements of Co- and Counter-current Fast-ion Losses in Forward and Reverse Magnetic Field in a Tokamak

Basil Duval, Ambrogio Fasoli, Pierre Lavanchy, Alexander Karpushov, Yanis Andrebe, Matthieu Toussaint, Matteo Vallar, Jesús Poley Sanjuán

A novel Fast Ion Loss Detector was designed, manufactured, installed and commissioned at the Tokamak & aacute; Configuration Variable. This is the first Fast Ion Loss Detector to feature four collimators that enable simultaneous detection of co- and counte ...

IOP Publishing Ltd2025

First measurements of velocity-space resolved intra-ELM fast-ion losses on the TCV tokamak

Basil Duval, Ambrogio Fasoli, Alexander Karpushov, Mario Ludovico Podesta, Benoît Labit, Umesh Kumar, Jesús Poley Sanjuán

Edge Localised Modes (ELMs) induced fast-ion losses have been characterised in the energy, E, and pitch, λ = v ∥ / v , space using a unique Fast Ion Loss Detector (FILD) on the tokamak à configuration variable. The FILD is equipped with a 128 Avalanche Pho ...

2025

Design and upgrades of the TCV fast ion loss detector

Basil Duval, Ambrogio Fasoli, Pierre Lavanchy, Alexander Karpushov, Yanis Andrebe, Augustin Charles Roger Philippe Clément, Matteo Vallar, Jesús Poley Sanjuán

The Tokamak à Configuration Variable has a unique Fast Ion Loss Detector (FILD) that allows the simultaneous measurement of co- and counter-current fast-ion losses in forward or reverse magnetic field. Recently, multiple novel upgrades have been implemente ...

AIP Publishing2025

Isotope effects in linear and saturated ohmic confinement of TCV tokamak and gyrokinetic validation

Basil Duval, Olivier Sauter, Henri Weisen, Stefano Coda, Alexander Karpushov, Benoît Labit, Lorenzo Martinelli, Dmytry Mykytchuk, Oleg Krutkin, Artur Perek

We investigated isotope effects during the tokamak à configuration variable (TCV) ohmic discharge of a diverted positive triangular shape configuration of deuterium (D) and hydrogen (H) plasmas. The transition from the linear ohmic confinement (LOC) regime ...

2025

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

Patrick Blanchard, Timothy Goodman, Jean-Marc Moret, Olivier Sauter, Holger Reimerdes, Stefano Coda, Alexander Karpushov, Yanis Andrebe, Duccio Testa, Benoît Labit, Christian Gabriel Theiler, Federico Alberto Alfredo Felici, Hugo De Oliveira, Claudio Marini, Antoine Pierre Emmanuel Alexis Merle, Anna Teplukhina, Joan Decker, Cedric Kar-Wai Tsui, Umar Sheikh, Cristian Galperti, Kevin Henricus Annemarie Verhaegh, Dahye Choi, Aylwin Iantchenko, Mengdi Kong, Roberto Maurizio, Francesco Carpanese, Mirko Wensing, Lorenzo Stipani, Federico Pesamosca, Olivier Claude Martin Février, Filippo Bagnato, Cristian Sommariva, Davide Galassi

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 ...

2025

L-H power threshold for neutral beam heated plasmas with Deuterium, Hydrogen, Helium and mixed ion species in TCV

Basil Duval, Yves Martin, Olivier Sauter, Alexander Karpushov, Benoît Labit, Alessandro Pau, Dmytry Mykytchuk, Artur Perek

A systematic study of the power threshold for L-H transition has been conducted in TCV. Only results from NB heated plasmas are reported. The dependencies of PLH on plasma current, plasma density and main ion species have been investigated. For Deuterium&# ...

IOP Publishing2025

Present status of heating neutral beam injection system at TCV

Patrick Blanchard, Basil Duval, Damien Fasel, Ambrogio Fasoli, Yves Martin, Olivier Sauter, Stefano Coda, Ugo Siravo, Alexander Karpushov, Yanis Andrebe, Jérémie Dubray, Frédéric Dolizy, Rémy Jacquier, Matthieu Toussaint, Dmytry Mykytchuk

The paper describes the operation and upgrade of the Heating Neutral Beam Injection (HNBI) system as well as the related infrastructure at the Tokamak Configuration Variable (TCV) during the last years. In 2023, the installation of new TCV neutron shieldin ...

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

Progress in the development of the ITER baseline scenario in TCV

Olivier Sauter, Stefano Coda, Alexander Karpushov, Yann Camenen, Benoît Labit, Antoine Pierre Emmanuel Alexis Merle, Olivier Claude Martin Février, Simon Van Mulders, Filippo Bagnato, Alessandro Pau, Matteo Vallar, Cassandre Ekta Contré, Stefano Marchioni, Oleg Krutkin, Reinart Andreas J. Coosemans

Under the auspices of EUROfusion, the ITER baseline (IBL) scenario has been jointly investigated on AUG and TCV in the past years and this paper reports on the developments on TCV. It is found that the performance of TCV IBL is mainly limited by (neoclassi ...

2024

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

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

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, , , , , , , , , , , , , , , , , , , , , , , ,

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

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, , , , , , , , , ,

Overview of the TCV digital real-time plasma control system and its applications

Basil Duval, Blaise Marlétaz, Olivier Sauter, Stefano Coda, Alexander Karpushov, Federico Alberto Alfredo Felici, Antoine Pierre Emmanuel Alexis Merle, Joan Decker, Marcelo Baquero Ruiz, Mengdi Kong, Francesco Carpanese, Federico Pesamosca, Anna Ngoc Minh Trang Vu, Alessandro Pau, Gino Marceca, Stefano Marchioni, Artur Perek

Real-time plasma control systems are at the heart of operation of modern tokamaks. The control system of the TCV tokamak has recently seen a major upgrade in terms of its hardware and software components. Control algorithms are entirely programmed and test ...

ELSEVIER SCIENCE SA2024

Excitation of toroidal Alfvén eigenmodes with counter-current NBI in the TCV tokamak

Alexander Karpushov, Laurie Porte, Matteo Vallar, Samuele Mazzi

In TCV, unstable modes excited by resonant interaction between the shear Alfvèn waves in con- tinuum gaps and energetic particles have been observed in scenarios with Neutral Beam Injection (NBI). TCV is a middle-size device (R 0 /a = 0.88/0.25) equipped w ...

IOP Publishing Ltd2023

TCV Tokamak Neutron Shielding Upgrade for Dual NBI Operation

Patrick Blanchard, Basil Duval, Henri Weisen, Alexander Karpushov, Duccio Testa, Jérémie Dubray, Antoine Pierre Emmanuel Alexis Merle, Matteo Vallar

The Tokamak a Configuration variable (TCV) is equipped with two neutral beam injection (NBI) systems delivering up to 1.2 MW each for pulse durations of up to 2 s. The first system (NBI1), designed for an injection energy in the range of 25 to 30 keV has b ...

2023

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

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

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

Overview of the TCV tokamak experimental programme

Patrick Blanchard, Stephan Brunner, Stefano Alberti, Basil Duval, Ambrogio Fasoli, Timothy Goodman, Xavier Llobet, Yves Martin, Jean-Marc Moret, Olivier Sauter, Henri Weisen, Ivo Furno, Holger Reimerdes, Jean-Philippe Hogge, Jan Horacek, Alexander Karpushov, Laurie Porte, Yanis Andrebe, Jonathan Graves, Duccio Testa, Benoît Labit, Joaquim Loizu Cisquella, Paolo Ricci, Christian Gabriel Theiler, Federico Alberto Alfredo Felici, Miguel Filipe Silva Füglister, Antoine Pierre Emmanuel Alexis Merle, Oulfa Chellaï, Curdin Tobias Wüthrich, Joan Decker, Cedric Kar-Wai Tsui, Pedro Andres Molina Cabrera, Matteo Fontana, Umar Sheikh, Cristian Galperti, Marcelo Baquero Ruiz, Dahye Choi, Aylwin Iantchenko, Mengdi Kong, Roberto Maurizio, Francesco Carpanese, , , , , , , , , , , , , , , , , , , , , , ,

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

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

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

Update of ion-optical system of neutral beam of Tokamak a Configuration Variable

Alexander Karpushov

An injector of fast deuterium atoms for plasma heating was designed and installed at the Tokamak a Configuration Variable (TCV). The neutral beam can deliver 1 MW power to the plasma in 2 s pulses. An ion beam of the injector is formed by a triode multisli ...

AMER INST PHYSICS2020