Publications associées à Solar energetic particles

Nonlinear interaction of Alfvénic instabilities and turbulence via the modification of the equilibrium profiles

Laurent Villard, Alberto Bottino, Xiao Wang

Nonlinear simulations of Alfvén modes (AMs) driven by energetic particles (EPs) in the presence of turbulence are performed with the gyrokinetic particle-in-cell code ORB5. The AMs carry a heat flux, and consequently they nonlinearly modify the plasma temp ...

Cambridge University Press2023

A hydrogenated amorphous silicon detector for Space Weather applications

Sylvain Dunand, Nicolas Würsch, Luca Massimiliano Antognini, Jonathan Emanuel Thomet, Matthew James Large

The characteristics of a hydrogenated amorphous silicon (a-Si:H) detector are presented here for monitoring in space solar flares and the evolution of strong to extreme energetic proton events. The importance and the feasibility to extend the proton measur ...

SPRINGER2023

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

Laurie Porte, Matteo Vallar, Alexander Karpushov, 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

How accurate are flux-tube (local) gyrokinetic codes in modeling energetic particle effects on core turbulence?

Olivier Sauter, Alberto Bottino, Emanuele Poli

Flux-tube (local) gyrokinetic codes are widely used to simulate drift-wave turbulence in magnetic confinement devices. While a large number of studies show that flux-tube codes provide an excellent approximation for turbulent transport in medium-large devi ...

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

Solar Wind Protons in the Diamagnetic Cavity at Comet 67P/Churyumov-Gerasimenko

Lucie Anemone Scharré

The plasma environment at a comet can be divided into different regions with distinct plasma characteristics. Two such regions are the solar wind ion cavity, which refers to the part of the outer coma that does not contain any solar wind ions anymore; and ...

AMER GEOPHYSICAL UNION2023

A novel measurement of marginal Alfven eigenmode stability during high power auxiliary heating in JET

Ambrogio Fasoli, Mario Ludovico Podesta, Paulo Giovane Paschoali Pereira Puglia

The interaction of Alfven eigenmodes (AEs) and energetic particles is one of many important factors determining the success of future tokamaks. In JET, eight in-vessel antennas were installed to actively probe stable AEs with frequencies ranging 25-250 kHz ...

IOP Publishing Ltd2022

Development of a reduced model for energetic particle transport by sawteeth in tokamaks

Mario Ludovico Podesta, Francesca Maria Poli, Anna Teplukhina, Matteo Vallar, Jiangyan Yang

The sawtooth instability is known for inducing transport and loss of energetic particles (EPs), and for generating seed magnetic islands that can trigger tearing modes. Both effects degrade the overall plasma performance. Several theories and numerical mod ...

2022

Construction of Fe3O4 bridged Pt/g-C3N4 heterostructure with enhanced solar to fuel conversion

Michael Graetzel, Shaik Mohammed Zakeeruddin

In this study, we report the effects of co-catalysts of Pt nanoparticles and Fe3O4 clusters on photocatalytic behaviors of g-C3N4 (CN) and the use of the resulting photocatalyst for CO2 photoreduction to solar fuels in a flow reactor operated at room-tempe ...

ELSEVIER2022

A Fast Ion Loss Detector for the TCV Tokamak

Lorenzo Stipani

A Fast Ion Loss Detector (FILD) was designed, assembled, installed and commissioned for TCV. This is a radially positionable, scintillator based detector that provides information on the 2D fast-ion velocity space lost at the probe's location. The collecte ...

EPFL2021

Nonlinear dynamics of energetic-particle driven geodesic acoustic modes in ASDEX Upgrade

Laurent Villard, Emmanuel Lanti, Alberto Bottino, Noé Thomas Elie Ohana, Emanuele Poli

Turbulence in tokamaks generates radially sheared zonal flows. Their oscillatory counterparts, geodesic acoustic modes (GAMs), appear due to the action of the magnetic field curvature. The GAMs can be driven unstable by an anisotropic energetic particle (E ...

AMER INST PHYSICS2020

Effect of the tangential NBI current drive on the stability of pressure and energetic particle driven MHD modes in LHD plasma

Wilfred Anthony Cooper, Joao Varela

The aim of the present study is to analyze the stability of the pressure gradient driven modes (PM) and Alfven eigenmodes (AE) in the large helical device (LHD) plasma if the rotational transform profile is modified by the current drive of the tangential n ...

IOP Publishing Ltd2020

Propulsion and energetics of a minimal magnetic microswimmer

Ignacio Pagonabarraga Mora

In this manuscript we describe the realization of a minimal hybrid microswimmer, composed of a ferromagnetic nanorod and a paramagnetic microsphere. The unbounded pair is propelled in water upon application of a swinging magnetic field that induces a perio ...

ROYAL SOC CHEMISTRY2020

Gyrokinetic simulations of toroidal Alfven eigenmodes excited by energetic ions and external antennas on the Joint European Torus

Ambrogio Fasoli, Duccio Testa, Patrick Blanchard, Mikhail Maslov, Paulo Giovane Paschoali Pereira Puglia, Ling Zhou

The gyrokinetic toroidal code (GTC) has been used to study toroidal Alfven eigenmodes (TAEs) in high-performance plasmas. Experiments performed at the Joint European Torus (JET), where TAEs were driven by energetic particles arising from neutral beams, ion ...

IOP Publishing Ltd2019

Modification of the Alfven wave spectrum by pellet injection

Olivier Sauter, Ambrogio Fasoli, Yiming Li, Basil Duval, Jonathan Graves, Duccio Testa, Patrick Blanchard, Henri Weisen, Federico Nespoli, Alessandro Pau, Federico Alberto Alfredo Felici, Hamish William Patten, Samuel Lanthaler, Cristian Sommariva, Soo-Jin Moon, Antoine Pierre Emmanuel Alexis Merle, Ricardo Lima, Haomin Sun, Michele Marin, Richard Pitts, Yann Camenen, Jan Horacek, Javier García Hernández, Marco Wischmeier, Nicola Vianello, Mikhail Maslov, Yao Zhou, Davide Galassi, Antonio José Pereira de Figueiredo, Emiliano Fable, Francesca Maria Poli, Daniele Brunetti, Anna Teplukhina, Alberto Mariani, Kenji Tanaka, Bernhard Sieglin, Otto Asunta, Gergely Papp, Leonardo Pigatto

Alfven eigenmodes driven by energetic particles are routinely observed in tokamak plasmas. These modes consist of poloidal harmonics of shear Alfven waves coupled by inhomogeneity in the magnetic field. Further coupling is introduced by 3D inhomogeneities ...

2019

Development and optimisation of advanced auxiliary ion heating schemes for 3D fusion plasma devices

Hamish William Patten

The magnetic confinement fusion devices known as the tokamak and the stellarator are progressing towards becoming viable commercial nuclear fusion reactor designs. Both ap- proaches require improvements in the applied heating sources and in the particle an ...

EPFL2019

Energetic ion losses 'channeling' mechanism and strategy for mitigation

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

Results from two different sets of JET experiments are presented. In experiments in which toroidicity-induced Alfven eigenmodes (TAEs) localized at different radial locations had the same frequencies and toroidal mode numbers, the occurrence of enhanced lo ...

2019

MHD spectroscopy of JET plasmas with pellets via Alfven eigenmodes

Olivier Sauter, Ambrogio Fasoli, Basil Duval, Stefano Coda, Martinus Gijs, Jonathan Graves, Yves Martin, Duccio Testa, Patrick Blanchard, Bruno Emanuel Ferreira De Sousa Correia, Alessandro Pau, Pierre-Thomas Paul Brun, Cristian Sommariva, Henri Weisen, Richard Pitts, Sun Hee Kim, Yann Camenen, Jan Horacek, Javier García Hernández, Marco Wischmeier, Mikhail Maslov, Nicola Vianello, Miguel Fernández Ruiz, Federico Nespoli, Antonio José Pereira de Figueiredo, Liang Yao, Yao Zhou, David Pfefferlé, Dalziel Joseph Wilson, Robin Humphry-Baker, Davide Galassi, José Pedro Rebelo Ferreira Marques, Ana Francisca Leal Silva Soares, Jonathan Marc Philippe Faustin, Daniel Scott Alessi, Arnout Lodewijk M Beckers, Julio Rodriguez, Hamish William Patten, Jonnathan Cesar Hidalgo Acosta, Samuel Lanthaler, , , , , , , ,

Synthetic NPA diagnostic for energetic particles in JET plasmas

Henri Weisen

Neutral particle analysis (NPA) is one of the few methods for diagnosing fast ions inside a plasma by measuring neutral atom fluxes emitted due to charge exchange reactions. The JET tokamak features an NPA diagnostic which measures neutral atom fluxes and ...

Iop Publishing Ltd2017

Stochastic modeling of snow transport and hydrologic response in alpine terrain

Francesco Comola

The scientific community has developed a keen interest in the processes driving the hydrologic cycle in alpine regions. The concern mainly stems from the vulnerability of snow-covered environments to the warming temperatures, such that entire ecological an ...

EPFL2017