Philippe Frédérique Bruno Guittienne

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Neutral Beam Injectors (NBI) for post-DEMO-like reactors must achieve a neutralization efficiency (fraction neutrals/ions) above 70%. To reach this, NBIs based on negative ions are necessary and an innovative concept of this type of injector is based on ph ...

This paper presents solutions for the classical one-dimensional (1D radial and Cartesian) problem of Langmuir probes in a collisionless, isothermal plasma. The method is based on two-fluid equations derived from the first two moments of Vlasov's equation. ...

This topical review gathers the last updates concerning caesium-free negative ion sources presented during the 63rd Course of the International school of Quantum Electronics of the Ettore Majorana Foundation and European collaborative works related to thes ...

In DEMO reactor to produce electricity, a total installed power up to 150 MW is considered. In the heating mix, neutral beam (NB) injectors of high neutral particle energy (0.8-1 MeV) with high wall-plug efficiency (η in the range of 50% to 60%) will be required. Present design considered a NB system delivering in total 50 MW. In the Siphore NB concept [1], one of the promising candidates to meet these challenging requirements, negative ions will be extracted from a long, thin ion source 3 m high and 15 cm

Helicon discharges are often considered somewhat mysterious, exhibiting experimental behaviors that are challenging to explain, such as abrupt plasma density jumps, hysteresis, and ‘blue core’ formation, among others. A significant part of the difficulty i ...

A large area antenna generates a plasma by both inductive and capacitive coupling; it is an electromagnetically coupled plasma source. In this work, experiments on a large area planar RF antenna source are interpreted in terms of a multi-conductor transmis ...

A helicon-based plasma source is under development and exploration at CEA-IRFM to produce an efficient and dense magnetized plasma column. The final objective of this development is the extraction and acceleration of a blade-like negative ion beam in view ...

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

Cavity Ring Down Spectroscopy (CRDS) is used to measure the D- absolute density produced in the helicon plasma reactor RAID (Resonant Antenna Ion Device) at the Swiss Plasma Center. The birdcage geometry of the helicon antenna produces a homogeneous, high- ...

We present the first results of electron density and temperature measurements obtained from Thomson scattering at the helicon plasma source (HPS) for the AWAKE project. These measurements are compared to simulation results from a 1D power and particle bala ...

In the next generation of fusion reactors, such as DEMO, neutral beam injectors (NBIs) of high energy (0.8-1 MeV) deuterium atom swith high wall-plug efficiency (>50%) will be required to reach burning plasma conditions and to provide a significant amount ...

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

Resonant antennas are increasingly employed by the plasma industry, and the theory has now developed alongside the technological applications to the extent that it is timely to document the progress in this field to aid antenna design for future novel RF p ...

Helicon sources are known to produce high-density plasmas and have found many applications. Different types of antenna have been used for helicon excitation but none of them generate a radio-frequency (rf) field that matches the helicon wave field determin ...

We report on the first 1D resolved two-photon absorption laser-induced fluorescence (TALIF) measurements of atomic hydrogen (H) performed in the Resonant Antenna Ion Device using a picosecond laser system. The results are obtained across a cylindrical plas ...

Helicon wave fundamental properties are explored experimentally and numerically in linear and toroidal geometries in the low-temperature plasma devices RAID and TORPEX. The helicon wave-plasma interaction is studied in terms of wave damping, propagation conditions in toroidal geometry, and nonlinear behavior.

The Advanced Wakefield Experiment (AWAKE), hosted at CERN, offers an innovative alternative to conventional radio frequency accelerators. Recent advances have strengthened the feasibility of this technique to provide particle energies relevant to future particle physics experiments [1].

A birdcage resonant helicon antenna is designed, mounted, and tested in the toroidal device TORPEX. The birdcage resonant antenna is an alternative to the usual Boswell or half-helical antenna designs commonly used for ∼ 10 cm diameter helicon sources in l ...

Philippe Frédérique Bruno Guittienne

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A double-ended helicon source to symmetrize RAID plasma

Two-fluid solutions for Langmuir probes in collisionless and isothermal plasma, over all space and bias potential

Latest experimental and theoretical advances in the production of negative ions in caesium-free plasmas

A novel helicon plasma source for negative ion beams for fusion

Helicon normal modes in radially non-uniform plasma column

Electromagnetic, complex image model of a large area RF resonant antenna as inductive plasma source

Magnetic field configurational study on a helicon-based plasma source for future neutral beam systems

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

Cavity ring-down spectroscopy to measure negative ion density in a helicon plasma source for fusion neutral beams

First Thomson scattering results from AWAKE’s helicon plasma source

Helicon wave-generated plasmas for negative ion beams for fusion

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

Resonant network antennas for radio-frequency plasma sources: Theory, technology and applications

Towards an optimal antenna for helicon waves excitation

Determination of atomic hydrogen density and fluorescence decay time by 1D resolved, picosecond TALIF in the RAID linear device

Helicon Wave-Plasma Interaction in Linear and Toroidal Geometries with Birdcage Resonant Antennas

Updates from the AWAKE Helicon Plasma Source: Plasma Diagnostics Driving Advances in Particle Acceleration

A birdcage resonant antenna for helicon wave generation in TORPEX

Etudes dynamiques du retournement de l'aimantation induit par un courant dans un nanofil ferro magnétique [i.e. ferromagnétique]