Publications de Cristian Sommariva

Milestone in predicting core plasma turbulence: successful multi-channel validation of the gyrokinetic code GENE

Basil Duval, Timothy Goodman, Olivier Sauter, Stefano Coda, Laurie Porte, Benoît Labit, Federico Alberto Alfredo Felici, Antoine Pierre Emmanuel Alexis Merle, Umar Sheikh, Mengdi Kong, Simon Van Mulders, Cristian Sommariva, Alessandro Pau

On the basis of several recent breakthroughs in fusion research, many activities have been launched around the world to develop fusion power plants on the fastest possible time scale. In this context, high-fidelity simulations of the plasma behavior on lar ...

2025

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

Basil Duval, Timothy Goodman, Olivier Sauter, Stefano Coda, Laurie Porte, Benoît Labit, Federico Alberto Alfredo Felici, Antoine Pierre Emmanuel Alexis Merle, Umar Sheikh, Mengdi Kong, Simon Van Mulders, Cristian Sommariva, Alessandro Pau

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 ...

Nature Research2025

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

Dynamics of JET runaway electron beams in D2-rich shattered pellet injection mitigation experiments

Olivier Sauter, Joan Decker, Cristian Sommariva, Alessandro Pau

The publication provide further insights into the dynamics of JET runaway electron (RE) beams mitigated by D2-rich shattered pellet injection (SPI) (Reux et al 2022 Plasma Phys. Control. Fusion 64 034002). Multi-diagnostic analyses show that mechanisms cau ...

IOP Publishing Ltd2024

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

Umar Sheikh, Mengdi Kong, Cristian Sommariva, Haomin Sun

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

Non-linear MHD modelling of transients in tokamaks: a review of recent advances with the JOREK code

Mengdi Kong, Cristian Sommariva

Transient magneto-hydrodynamic (MHD) events like edge localized modes (ELMs) or disruptions are a concern for magnetic confinement fusion power plants. Research with the MHD code JOREK towards understanding control of such instabilities is reviewed here in ...

IOP Publishing Ltd2024

Observation of magnetic islands in tokamak plasmas during the suppression of edge-localized modes

Basil Duval, Timothy Goodman, Olivier Sauter, Stefano Coda, Laurie Porte, Benoît Labit, Federico Alberto Alfredo Felici, Antoine Pierre Emmanuel Alexis Merle, Umar Sheikh, Mengdi Kong, Cristian Sommariva, Alessandro Pau

In tokamaks, a leading platform for fusion energy, periodic filamentary plasma eruptions known as edge-localized modes occur in plasmas with high-energy confinement and steep pressure profiles at the plasma edge. These edge-localized modes could damage the ...

2024

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

Overview of T and D-T results in JET with ITER-like wall

Olivier Sauter, Holger Reimerdes, Duccio Testa, Benoît Labit, Umar Sheikh, Olivier Claude Martin Février, Eduardo José Lascas Neto, Cristian Sommariva, Alessandro Pau, Matteo Vallar, Gino Marceca, Cassandre Ekta Contré, Mackenzie Peter-Fulford Van Rossem, Samuele Mazzi

In 2021 JET exploited its unique capabilities to operate with T and D-T fuel with an ITER-like Be/W wall (JET-ILW). This second major JET D-T campaign (DTE2), after DTE1 in 1997, represented the culmination of a series of JET enhancements-new fusion diagno ...

IOP Publishing Ltd2024

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

Patrick Blanchard, Ambrogio Fasoli, Olivier Sauter, Henri Weisen, Duccio Testa, Federico Alberto Alfredo Felici, Umar Sheikh, Paulo Giovane Paschoali Pereira Puglia, Eduardo José Lascas Neto, Cristian Sommariva, Davide Galassi, Mike Machielsen, Alessandro Pau, Gino Marceca

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 ...

Nature Research2024

Overview of ASDEX upgrade results in view of ITER and DEMO

Basil Duval, Timothy Goodman, Olivier Sauter, Stefano Coda, Benoît Labit, Federico Alberto Alfredo Felici, Antoine Pierre Emmanuel Alexis Merle, Umar Sheikh, Mengdi Kong, Simon Van Mulders, Cristian Sommariva, Alessandro Pau

Experiments on ASDEX Upgrade (AUG) in 2021 and 2022 have addressed a number of critical issues for ITER and EU DEMO. A major objective of the AUG programme is to shed light on the underlying physics of confinement, stability, and plasma exhaust in order to ...

IOP Publishing Ltd2024

Magnetic control of tokamak plasmas through deep reinforcement learning

Basil Duval, Ambrogio Fasoli, Jean-Marc Moret, Olivier Sauter, Stefano Coda, Jonas Buchli, Federico Alberto Alfredo Felici, Antoine Pierre Emmanuel Alexis Merle, Cristian Galperti, Francesco Carpanese, Federico Pesamosca, Cristian Sommariva, Jonas Degrave, Brendan Tracey

Nuclear fusion using magnetic confinement, in particular in the tokamak configuration, is a promising path towards sustainable energy. A core challenge is to shape and maintain a high-temperature plasma within the tokamak vessel. This requires high-dimensi ...

2022

Heavy impurity transport in tokamaks subject to plasma rotation, NTV and the influence of saturated ideal MHD perturbations

Jonathan Graves, Eduardo José Lascas Neto, Cristian Sommariva

Strongly peaked tungsten accumulation is a common feature of high performance plasma scenarios in JET with the ITER-like wall, particularly during MHD activity induced by m/n = 1/1 continuous modes. This study investigates the effect of 1/1 long living int ...

2022

Physics of runaway electrons with shattered pellet injection at JET

Javier García Hernández, Cristian Sommariva, Gergely Papp

Runaway electrons (REs) created during tokamak disruptions pose a threat to the reliable operation of future larger machines. Experiments using shattered pellet injection (SPI) have been carried out at the JET tokamak to investigate ways to prevent their g ...

2022

Overview of JET results for optimising ITER operation

Patrick Blanchard, Ambrogio Fasoli, Olivier Sauter, Henri Weisen, Jonathan Graves, Duccio Testa, Federico Alberto Alfredo Felici, Matteo Fontana, Umar Sheikh, Paulo Giovane Paschoali Pereira Puglia, Eduardo José Lascas Neto, Cristian Sommariva, Davide Galassi, Mike Machielsen, Alessandro Pau, Gino Marceca

The JET 2019-2020 scientific and technological programme exploited the results of years of concerted scientific and engineering work, including the ITER-like wall (ILW: Be wall and W divertor) installed in 2010, improved diagnostic capabilities now fully a ...

IOP Publishing Ltd2022

Progress from ASDEX Upgrade experiments in preparing the physics basis of ITER operation and DEMO scenario development

Basil Duval, Timothy Goodman, Olivier Sauter, Stefano Coda, Laurie Porte, Benoît Labit, Federico Alberto Alfredo Felici, Antoine Pierre Emmanuel Alexis Merle, Umar Sheikh, Cristian Sommariva, Alessandro Pau

An overview of recent results obtained at the tokamak ASDEX Upgrade (AUG) is given. A work flow for predictive profile modelling of AUG discharges was established which is able to reproduce experimental H-mode plasma profiles based on engineering parameter ...

IOP Publishing Ltd2022

The JOREK non-linear extended MHD code and applications to large-scale instabilities and their control in magnetically confined fusion plasmas

Sun Hee Kim, Fang Liu, Cristian Sommariva

JOREK is a massively parallel fully implicit non-linear extended magneto-hydrodynamic (MHD) code for realistic tokamak X-point plasmas. It has become a widely used versatile simulation code for studying large-scale plasma instabilities and their control an ...

IOP Publishing Ltd2021

A novel path to runaway electron mitigation via deuterium injection and current-driven MHD instability

Cristian Sommariva

Relativistic electron (RE) beams at high current density (low safety factor, q ( a )) yet very low free-electron density accessed with D-2 secondary injection in the DIII-D and JET tokamak are found to exhibit large-scale MHD instabilities that benignly te ...

IOP Publishing Ltd2021

RF sheath modeling of experimentally observed plasma surface interactions with the JET ITER-Like Antenna

Patrick Blanchard, Basil Duval, Ambrogio Fasoli, Yves Martin, Richard Pitts, Olivier Sauter, Henri Weisen, Stefano Coda, Marco Wischmeier, Jan Horacek, Yann Camenen, Jonathan Graves, Duccio Testa, Mikhail Maslov, Javier García Hernández, David Pfefferlé, Dalziel Joseph Wilson, Jonathan Marc Philippe Faustin, Federico Nespoli, Hamish William Patten, Nicola Vianello, Antonio José Pereira de Figueiredo, Samuel Lanthaler, Liang Yao, Cristian Sommariva, Davide Galassi, Alessandro Pau, Yao Zhou, Otto Asunta, Bernhard Sieglin

Waves in the Ion Cyclotron Range of Frequencies (ICRF) enhance local Plasma-Surface Interactions (PSI) near the wave launchers and magnetically-connected objects via Radio-Frequency (RF) sheath rectification. ITER will use 20MW of ICRF power over long puls ...

Elsevier2019

Determination of tungsten sources in the JET-ILW divertor by spectroscopic imaging in the presence of a strong plasma continuum

Patrick Blanchard, Basil Duval, Ambrogio Fasoli, Yves Martin, Richard Pitts, Olivier Sauter, Henri Weisen, Stefano Coda, Marco Wischmeier, Jan Horacek, Yann Camenen, Jonathan Graves, Duccio Testa, Mikhail Maslov, Javier García Hernández, David Pfefferlé, Jonnathan Cesar Hidalgo Acosta, Dalziel Joseph Wilson, Jonathan Marc Philippe Faustin, Federico Nespoli, Alberto Hernando de Castro, Hamish William Patten, Li Shuai, Nicola Vianello, Antonio José Pereira de Figueiredo, Samuel Lanthaler, Liang Yao, Cristian Sommariva, Davide Galassi, Alessandro Pau, Yao Zhou, Otto Asunta, Bernhard Sieglin

The identification of the sources of atomic tungsten and the measurement of their radiation distribution in front of all plasma-facing components has been performed in JET with the help of two digital cameras with the same two-dimensional view, equipped wi ...

Elsevier2019