Publications by Jérémy Genoud

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Parasitic oscillations excitation is one of the main point hindering high-power gyrotron operation for fusion application. These instabilities, besides being dangerous for the gyrotron components, could possibly degrade the electron beam quality before it ...

Gyrotron R&D within the EUROfusion Work Package Heating and Current Drive (WPHCD) is addressing the challenging requirements posed on gyrotrons by the European concept for a demonstration fusion power plant (EU DEMO). These requirements, as specified withi ...

Tokamak à configuration variable (TCV), recently celebrating 30 years of near-continual operation, continues in its missions to advance outstanding key physics and operational scenario issues for ITER and the design of future power plants such as DEMO. The ...

In Europe, the research and development with main focus on achieving robust industrial designs of series gyrotrons for electron cyclotron heating and current drive of today's nuclear fusion experiments and towards a future DEMOnstration fusion power plant ...

The ionization of the residual gas in gyrotrons causes the generation of positively charged ions and negatively charged electrons. Using the electron optics code Ariadne, it was possible to simulate the behavior of these electrons in the overall gyrotron g ...

Gyrotrons are essential devices for the development of nuclear fusion, but their design and reliable operation still present numerous challenges. In particular, certain gyrotrons encounter issues related to trapped electron clouds in the magnetron injectio ...

A model is presented for simulating the electron beam within the entire gyrotron geometry using an electron optics code. The model incorporates the influence of the electromagnetic fields generated by the cavity's operational mode through a simple self-con ...

Gyrotrons are high-power microwave sources, readily applied in diverse fields ranging from fusion research and thermal treatment of materials to advanced spectroscopic techniques. Here, we provide the cavity design of a 198 GHz gyrotron to generate microwa ...

A numerical model is presented to describe the electron beam neutralization during long-pulse and continuous-wave operation in gyrotrons. This model has been implemented in the electrostatic, self-consistent electron optics code Ariadne. Using this model, ...

Efficiency is a key factor for high-power gyrotrons, particularly in future fusion power plants, where a large number of gyrotron units will be required for plasma heating. A single-stage depressed collector enhances efficiency from approximately 35% to 50 ...

A dual-frequency gyrotron has been developed within the context of the recent Tokamak à Configuration Variable (TCV) upgrade. The gyrotron is designed to generate a 1 MW, 2 seconds RF wave at 84 or 126 GHz. Before integrating the gyrotrons in the TCV tokam ...

Hyperpolarization in diamond via dynamic nuclear polarization (DNP) has attracted a lot of interest for various applications as diamond exhibits extremely long C-13 spin relaxation times and has endogenous polarizing agents in the form of crystalline defec ...

An 1 MW long-pulse (2s), 84/126 GHz dual frequency gyrotron has been produced by THALES MSI, France responding to the needs for upgrading the ECH system of the TCV tokamak The initial tests of the prototype carried out at EPFL, Switzerland, have verified a ...

This paper presents the new 2D electrostatic particle -in -cell code FENNECS developed to study the formation of magnetized non -neutral plasmas in geometries with azimuthal symmetry. This code has been developed in the domain of gyrotron electron gun desi ...

The self-consistent simulation of the electron beam interaction was performed in the presence of a lossy dielectric layer in the smooth-wall beam duct of a gyrotron oscillator. For this purpose, the linear and spectral code TWANGlinspec was extended. In th ...

In order to study parasitic oscillation that may occur in a realistic beam duct upstream to the gyrotron cavity, the self-consistent linear and spectral code TWANGlinspec has been modified. The large inhomogeneities in the smooth-wall beam duct geometry or ...

A significant effort has recently been initiated at ETHZ for the development of high frequency, high power, frequency-agile gyrotrons for DNP-NMR spectroscopy. In this context an in house cavity interaction code is under development. In this paper, some de ...

In the frame of the TCV Tokamak upgrade, two 84/126 GHz/2 s dual frequency gyrotrons designed by SPC and KIT and manufactured by THALES will be added to the existing EC-System. The first unit has been delivered to EPFL-SPC and tested. In the commissioning ...

The first unit of the dual-frequency gyrotron, 84-126GHz/lMW/2s, for the upgrade of the TCV ECH system has been delivered and is presently being commissioned. During a first phase, long-pulse operation (TRF>0.5s) has been achieved and powers in excess of 0 ...

Using the new interaction code Phaedra, a thorough and systematic investigation of the operation of a high-power gyrotron cavity in the hard excitation regime took place. The preliminary result of this analysis shows that in the hard excitation regime, the ...

Jérémy Genoud

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Advanced linear models for gyro-backward wave instabilities in gyrotrons

Overview of recent gyrotron R&D towards DEMO within EUROfusion Work Package Heating and Current Drive

Experimental research on the TCV tokamak

From W7-X Towards ITER and Beyond: 2019 Status on EU Fusion Gyrotron Developments

Study of Ionized Particles in a Gyrotron Using a Full Gyrotron Simulation Model

Electron trapping in gyrotron electron guns: Validation of the FENNECS code with the T-REX experiment

Electron optics simulation in the overall gyrotron geometry

Cavity Design for a High-Power, Frequency-Agile 198 GHz Gyrotron

A model of electron beam neutralization for gyrotron simulations

Effects of reflected electrons on the efficiency of high-power gyrotrons

Experimental characterization of the TCV dual-frequency gyrotron and validation of numerical codes including the effect of After Cavity Interaction

High-Field C-13 Dynamic Nuclear Polarization in Nanodiamond

Manufacturing and Test of the 1 MW Long-Pulse 84/126 GHz Dual-Frequency Gyrotron for TCV

FENNECS: a novel particle-in-cell code for simulating the formation of magnetized non-neutral plasmas trapped by electrodes of complex geometries

Modeling of parasitic oscillations in smooth-wall circular symmetric dielectric-loaded gyrotron beam ducts

Parasitic Oscillations in Smooth-Wall Circular Symmetric Gyrotron Beam Ducts

Development of Kilowatt THz Gyrotrons for Pulsed Dynamic Nuclear Polarization - Cavity Design Code Phaedra -

Megawatt power generation of the dual-frequency gyrotron for TCV at 84 and 126 GHz, in long pulses

High-efficiency, long-pulse operation of MW-level dual-frequency gyrotron, 84/126GHz, for the TCV Tokamak

Thorough Simulation of High-Power Gyrotron Cavity Interaction in the Hard Excitation Regime