Concept

Propulseur à force pondéromotrice

Publications associées (18)

Impact of resonant second-harmonic generation on helicon-wave damping

Ivo Furno, Stephan Brunner, Philippe Frédérique Bruno Guittienne

Collisional dissipation is expected to be the primary damping mechanism for helicon waves in low-temperature, high-density, moderate magnetic field plasmas. Combining a normal-mode analysis with high-resolution magnetic field measurements, we validate this expectation across a broad parameter space. However, we identify a distinct regime where the measured helicon damping rate is reduced by nearly a factor of 2 compared with collisional predictions. In this regime, a second harmonic at 2ω is observed, contr

2026

High resolution incoherent Thomson scattering diagnostic for the Resonant Antenna Ion Device (RAID) helicon plasmas

Ivo Furno, Philippe Frédérique Bruno Guittienne

We present a recent upgrade of the incoherent Thomson scattering (TS) diagnostic for the Resonant Antenna Ion Device (RAID), a linear plasma source based on helicon excitation operated at the Swiss Plasma Center at Ecole Polytechnique Fédérale de Lausanne. By operating in the visible range, which facilitates the recording of the spectrally resolved TS signal with a gated camera, this system has greatly enhanced the ability to characterize the plasmas generated by RAID in argon, helium, deuterium, and hydrog

AIP Publishing2026

Recent progress with Diagnostic Neutral Beam Injector at TCV tokamak

Stefano Coda, Basil Duval, Yves Martin, Damien Fasel, Ugo Siravo

The present status of operation and upgrades of the 50 keV / 3 A Diagnostic Neutral Beam Injector (DNBI) at TCV tokamak are described. The plasma grid was replaced by a new re-manufactured one with its existing design. The technology and production were performed within SPC-EPFL. The further redesign of the plasma grid was done to improve the strength and stability, accounting for the results of grid deformation measurements, and considering ANSYS thermomechanical analysis in combination with IBSimu beam si

IOP Publishing2026

First Demonstration of Resonant Pitch-Angle Scattering of Relativistic Electrons by Externally Launched Helicon Waves

Helicon waves (also known as whistler waves) satisfying the normal wave-particle cyclotron resonance are observed to limit the growth and maximum energy of relativistic electrons (REs) in low-density Ohmic DIII-D tokamak plasmas. Following the application of helicon waves, pitch-angle scattering of high-energy REs causes an increase in both synchrotron and electron-cyclotron emissions. The hard x-ray emission, a proxy for the RE population, ceases to grow. Energy-resolved hard x-ray measurements also show a

2026

Acceleration of Solvers for Plasma Simulation in the Tokamak Boundary

Simulating turbulence in the tokamak boundary, which is crucial for understanding and optimizing future fusion power plants performance, is computationally challenging due to the complex, multi-physics, and multi-scale nature of plasma dynamics. In the boundary region, plasma interacts with neutral particles recycled from the walls, leading to nonlinear phenomena that control confinement and heat exhaustion. Accurately capturing these coupled processes requires solving large-scale, stiff, and non-local pro

EPFL2026

Investigation of surface charging characteristics of ion-irradiated alumina ceramics: Transition from secondary electron emission to charge injection

Abnormal electrical breakdowns have been observed in the grid system of ion thrusters during both ground tests and space missions, leading to severe discharge-induced damage. Alumina ceramic, commonly used as an insulating material in grid systems, is subject to surface modification under ion beam irradiation, which in turn significantly alters its surface charging behavior. In this study, we systematically investigated the charging characteristics of alumina ceramics after Xe+ ion irradiation, including tr

AIP Publishing2025

Ion heating and flows in a high power helicon source

Ivo Furno, Alan Howling, Rémy Jacquier, Riccardo Agnello, Gennady Plyushchev

We report experimental measurements of ion temperatures and flows in a high power, linear, magnetized, helicon plasma device, the Resonant Antenna Ion Device (RAID). Parallel and perpendicular ion temperatures on the order of 0.6 eV are observed for an rf ...

Amer Inst Physics2017

Assessment of Neutron Production in Neutral Beam Injector of TCV Tokamak

Alexander Karpushov

Neutral beam (NB) injector for the TCV tokamak has been designed to produce a deuterium beam with energy 30 keV, equivalent current up to 50 A, and pulse duration 2 s. The injector operation is accompanied by generation of fast neutrons produced in deuteri ...

Amer Inst Physics2016

Kinetic Theory and Vlasov Simulation of Nonlinear Ion-Acoustic Waves in Multi-Ion Species Plasmas

Stephan Brunner

The theory of damping and nonlinear frequency shifts from particles resonant with ion-acoustic waves (IAWs) is presented for multi-ion species plasma and compared to driven wave Vlasov simulations. Two distinct IAW modes may be supported in multi-ion speci ...

Amer Physical Soc2013

Production of molecular sideband radioisotope beams at CERN-ISOLDE using a Helicon-type plasma ion source

In order to account for the increasing demand for strong molecular beams for nuclear physics experiments at ISOLDE, a new radioactive ion source concept based on an RE discharge in a magnetized plasma was developed at CERN. Experimental studies at the ISOL ...

Elsevier Science Bv2013

Tokamak SOL fluid simulations with self-consistent boundary conditions at the magnetic presheath edge

Fluid codes simulating the dynamics of magnetized plasmas with field lines terminating on the device vessel require boundary conditions that are consistent with the plasma-wall transition region. When the magnetic field strikes the wall at an oblique angle, this transition region corresponds to the magnetic presheath entrance (MPE). A complete analytical set of boundary conditions at the MPE is provided here for the density, temperature, potential, vorticity, and parallel ion and electron velocities, that i

2012

Realization of a solid-propellant based microthruster using low temperature co-fired ceramics

Thomas Maeder, Peter Ryser

The introduction of micro-spacecrafts in the space industry has led to the development of various micro-propulsion techniques. Microthrusters are micropropulsion devices used in a microspacecraft for precise station keeping, orbit adjustment, attitude control, drag compensation and apogee kicking. The principle of operation of a solid propellant thruster is based on the combustion of a solid energetic material stored in a microfabricated chamber. In the current work, Low-Temperature Co-fired Ceramic (LTCC)

2010

Performance of a micro-fabricated Colloid thruster system

In order to fully characterize the performance of the colloid thruster system the electrospray (ES) beam must itself be fully characterized. This may be achieved by measuring various properties such as flow rate, current, droplet/ion charge to mass ratio and current profile. Beam properties of both standard electrospray mass spectrometry (ESMS) emitters and arrays of custom made micro-fabricated emitters have been determined. By varying the geometries of the micro-fabricated emitters two basic modes of thru

2009

Future thruster application: combination of numerical simulation of ECR zone and plasma X-ray Bremsstrahlung measurement of the SWISSCASE ECR ion source

We present the combination of the numerical 3D magnetic field simulation of SWISSCASE, the new 10 GHz ECR ion source at the University of Bern in Switzerland, and the experimental X-ray Bremsstrahlung measurement of the same ion source, to determine the hot electron and the total electron number densities of its ECR plasma. The results, which are in excellent agreement with literature, demonstrate the quality of the numerical simulation, the X-ray Bremsstrahlung measurement and the method of combination to

2009

Micromachined electrospray thrusters for spacecraft propulsion

Micromachining has enabled the downscaling of large, massive and power hungry systems into small batch-produced integrated devices. Recent progress in electrospray thruster technology, in particular the discovery of an ionic emission mode using the ionic l ...

EPFL2009

SWISSCASE : development and characterization of an electron cyclotron resonance ion source for the calibration of space flight instruments

This PhD thesis consists of planning, simulating, building, testing and characterizing a new electron cyclotron resonance (ECR) ion source, SWISSCASE. the Solar Wind Ion Source Simulator for the CAlibration of Space Experiments located at the University of ...

EPFL2008

Focusing and continuous separation of cells in a microfluidic device using lateral dielectrophoresis

Philippe Renaud

We have fabricated a microfluidic device based on a novel geometrical arrangement of lateral metal electrodes and a patterned insulator. We have used the concept of insulator-based "electrodeless" dielectrophoresis to achieve focusing and continuous separation of dielectric particles flowing down a channel. The novelty consists of generating several electric fields in the structure which allow getting multiple opposite dielectrophoresis with a controllable position of equilibrium. Two and three dielectropho

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2007

Shaped electrode and lens for a uniform radio-frequency capacitive plasma

Laurent Fabien Hubert Sansonnens

Plasma inhomogeneity caused by standing-wave effects in rf parallel plate reactors can be removed if one of the electrodes is replaced by a shaped electrode. The proposed shape is calculated using Maxwell's equations in vacuum. In this solution, the electric field has a radially uniform vertical component, and a radial component which remains negligible for a plasma gap small compared to the quarter wavelength. Perturbations to this vacuum solution in presence of a plasma should remain small if the damping

2003

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Publications associées (18)

Investigation of surface charging characteristics of ion-irradiated alumina ceramics: Transition from secondary electron emission to charge injection

AIP Publishing2025

Future thruster application: combination of numerical simulation of ECR zone and plasma X-ray Bremsstrahlung measurement of the SWISSCASE ECR ion source

2009

Micromachined electrospray thrusters for spacecraft propulsion

EPFL2009

SWISSCASE : development and characterization of an electron cyclotron resonance ion source for the calibration of space flight instruments

EPFL2008

Focusing and continuous separation of cells in a microfluidic device using lateral dielectrophoresis

Philippe Renaud

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2007

Shaped electrode and lens for a uniform radio-frequency capacitive plasma

Laurent Fabien Hubert Sansonnens

2003