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1. A birdcage resonant antenna for helicon wave generation in TORPEX

Author

Vincent, Simon, Guittienne, Philippe, Quigley, Patrick, Sepulchre, Cyrille, Jacquier, Rémy, Bertizzolo, Robert, Baquero-Ruiz, Marcelo, Howling, Alan A., and Furno, Ivo

Subjects
Physics - Plasma Physics
Abstract

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 $\sim$ 10 cm diameter helicon sources in low temperature plasma devices. The main advantage of the birdcage antenna lies in its resonant nature, which makes it easily operational even at large scales, an appealing feature for the TORPEX device whose poloidal cross section is 40 cm in diameter. With this antenna helicon waves are shown to be launched and sustained throughout the whole torus of TORPEX. The helicon waves can be launched at low power on a pre-existing magnetron-generated plasma with little effect on the density profiles. The birdcage antenna can also be used alone to produce plasma, which removes the constraint of a narrow range of applied magnetic fields required by the magnetron, opening the way to a new range of studies on TORPEX with the external magnetic field as a control parameter.

Published
2024

12. Introduction

Author

Guittienne, Philippe, primary, Howling, Alan, additional, and Furno, Ivo, additional

Published
2024
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17. Helicon Volume Production of H− and D− Using a Resonant Birdcage Antenna on RAID

Author

Furno, Ivo, Agnello, Riccardo, Howling, Alan, Guittienne, Philippe, Jacquier, Remy, Stollberg, Christine, Baquero, Marcelo, Kadi, Lyes, Marini, Claudio, Han, Jia, Béchu, Stéphane, Fubiani, Gwenael, Simonin, Alain, Taccogna, Francesco, Drake, Gordon W. F., Editor-in-Chief, Babb, James, Series Editor, Bandrauk, Andre D., Series Editor, Bartschat, Klaus, Series Editor, Joachain, Charles J., Series Editor, Keidar, Michael, Series Editor, Lambropoulos, Peter, Series Editor, Leuchs, Gerd, Series Editor, Velikovich, Alexander, Series Editor, and Bacal, Marthe, editor

Published
2023
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18. Helicon Volume Production of H− and D− Using a Resonant Birdcage Antenna on RAID

Author

Furno, Ivo, primary, Agnello, Riccardo, additional, Howling, Alan, additional, Guittienne, Philippe, additional, Jacquier, Remy, additional, Stollberg, Christine, additional, Baquero, Marcelo, additional, Kadi, Lyes, additional, Marini, Claudio, additional, Han, Jia, additional, Béchu, Stéphane, additional, Fubiani, Gwenael, additional, Simonin, Alain, additional, and Taccogna, Francesco, additional

Published
2022
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19. A birdcage resonant antenna for helicon wave generation in TORPEX.

Author

Vincent, Simon P. H., Guittienne, Philippe, Quigley, Patrick, Sepulchre, Cyrille, Jacquier, Rémy, Bertizzolo, Robert, Baquero-Ruiz, Marcelo, Howling, Alan A., and Furno, Ivo

Subjects
LOW temperature plasmas, ANTENNA design, ANTENNAS (Electronics), BIRDCAGES, MAGNETIC control
Abstract

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 low temperature plasma devices. The main advantage of the birdcage antenna lies in its resonant nature, which makes it easily operational even at large scales, an appealing feature for the TORPEX device whose poloidal cross section is 40 cm in diameter. With this antenna, helicon waves are shown to be launched and sustained throughout the whole torus of TORPEX. The helicon waves can be launched at low power on a pre-existing magnetron-generated plasma with little effect on the density profiles. The birdcage antenna can also be used alone to produce plasma, which removes the constraint of a narrow range of applied magnetic fields required by the magnetron, opening the way to a new range of studies on TORPEX with the external magnetic field as a control parameter. [ABSTRACT FROM AUTHOR]

Published
2024
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20. Implementing water recirculation in a novel portable plasma-activated water reactor enhances antimicrobial effect against Escherichia coli

Author

Agus, R, Avino, F, Ibba, L, Myers, B, Zampieri, L, Martines, E, Howling, A, Furno, I, Agus, Rita, Avino, Fabio, Ibba, Lorenzo, Myers, Brayden, Zampieri, Leonardo, Martines, Emilio, Howling, Alan, Furno, Ivo, Agus, R, Avino, F, Ibba, L, Myers, B, Zampieri, L, Martines, E, Howling, A, Furno, I, Agus, Rita, Avino, Fabio, Ibba, Lorenzo, Myers, Brayden, Zampieri, Leonardo, Martines, Emilio, Howling, Alan, and Furno, Ivo

Abstract

The need for sustainable and reliable decontamination methods is driven by concerns regarding antibiotic resistance, as well as environmental and cost-efficiency challenges associated with traditional methods. Plasma-activated water (PAW) holds significant promise as an innovative and eco-friendly decontamination method. Nevertheless, prior to industrial implementation of PAW-based decontamination devices, a deep understanding of the bacterial inactivation mechanisms and its interplay with PAW chemical composition is required. Advancing in this field requires interdisciplinary and collaborative research using standardized practices with cost-effective and shareable PAW reactors that are still missing today. Here, to this end, a portable PAW reactor, featuring a surface dielectric barrier discharge (SDBD) that operates in air, is presented. The gaseous and aqueous phases were chemically characterized by Fourier transform infrared (FTIR) absorption spectroscopy and vis-spectrophotometry, respectively. To assess PAW antimicrobial efficacy Escherichia coli was employed as a model organism on six different PAW samples for three different treatment times. The significance of water recirculation in controlling the chemical composition of PAW, altering the nitrogen species balance in favor of NO2−, is demonstrated. This chemical modification consequently enhanced the antimicrobial effectiveness of PAW, reaching a log reduction of ∼6. Exposing E. coli to equivalent concentrations of RONS to those found in PAW attained similar log-reductions, indicating that acidified nitrites are key to PAW antimicrobial activity. Through an innovative and portable design, this study illustrates the crucial role of water recirculation in tailoring PAW composition, leading to improved decontamination capabilities and establishing a key parameter for further optimization of PAW production.

Published
2024

30. Helicon wave-generated plasmas for negative ion beams for fusion

Author

Furno Ivo, Agnello Riccardo, Fantz U., Howling Alan, Jacquier Remy, Marini Claudio, Plyushchev Gennady, Guittienne Philippe, and Simonin Alain

Subjects
Physics, QC1-999
Abstract

In the next generation of fusion reactors, such as DEMO, neutral beam injectors (NBIs) of high energy (0.8-1 MeV) deuterium atoms with high wall-plug efficiency (>50%) will be required to reach burning plasma conditions and to provide a significant amount of current drive. The present NBI system for DEMO assumes that 50 MW is delivered to the plasma by 3 NBIs. In the Siphore NBI concept, negative deuterium ions are extracted from a long, thin ion source 3 m high and 15 cm wide, accelerated and subsequently photo-neutralized. This requires the development of a new generation of negative ion sources. At the Swiss Plasma Center, a novel radio frequency helicon plasma source, based on a resonant network antenna source delivering up to 10 kW at 13.56 MHz, has been developed and is presently under study on the Resonant Antenna Ion Device (RAID). RAID is a linear device (1.9 m total length, 0.4 m diameter) and is equipped with an extensive set of diagnostics for full plasma characterization. In this work, the principles of operation of resonant antennas as helicon sources are introduced. We present absolute spectroscopy, Langmuir probe, and interferometry measurements on helicon plasmas. We characterize the performance of the source in terms of hydrogen/deuterium dissociation and negative ion production as a function of the input power. Furthermore, first results with the helicon birdcage antenna installed on the Cybele negative ion source at CEA-IRFM are presented, as a first step towards the validation of the Siphore concept.

Published
2017
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31. Entering the plasma agriculture field: An attempt to standardize protocols for plasma treatment of seeds

Author

Waskow, Alexandra, Avino, Fabio, Howling, Alan, Furno, Ivo, Waskow, Alexandra, Avino, Fabio, Howling, Alan, and Furno, Ivo

Abstract

Plasma treatments are currently being assessed as a seed processing technology for agricultural purposes. There is sufficient information as a proof-of-concept, but a lack of standardization in the methodology prevents a convincing evaluation of plasma treatment on seeds. It would be helpful to coordinate research efforts to make the entry for newcomers into this interdisciplinary field less overwhelming and to aid in transferring this technology into the industry by establishing a common protocol. This review presents the parameters used in the seed preparation, the plasma treatment of the seed, and the seed posttreatment. This summary of the plasma and biological parameters is intended to raise awareness about questions that need to be addressed to properly record protocol details and reproduce results for the plasma treatment of seeds.

Published
2021
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32. Mechanisms of Plasma-Seed Treatments as a Potential Seed Processing Technology

Author

Waskow, Alexandra, Howling, Alan, Furno, Ivo, Waskow, Alexandra, Howling, Alan, and Furno, Ivo

Abstract

Plasma treatments are currently being assessed as a seed processing technology for agricultural purposes where seeds are typically subjected to pre-sowing treatments to improve the likelihood of timely and uniform germination. The aim of this review is to summarize the hypotheses and present the evidence to date of how plasma treatments affect seeds, considering that there is difficulty in standardizing the methodology in this interdisciplinary field given the plethora of variables in the experimental setup of the plasma device and handling of biological samples. The ever increasing interest for plasma agriculture drives the need for a review dedicated to seeds, which is understandable to an interdisciplinary audience of biologists and plasma physicists. Seeds are the first step of the agricultural cycle and at this stage, the plant can be given the highest probability of establishment, despite environmental conditions, to exploit the genetic potential of the seed. Furthermore, seedlings seem to be too sensitive to the oxidation of plasma and therefore, seeds seem to be the ideal target. This review intentionally does not include seed disinfection and sterilization due to already existing reviews. Instead, a summary of the mechanisms of how plasma may be affecting the seed and its germination and developmental properties will be provided and discussed.

Published
2021
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35. High Voltage Electrical Power System Architecture optimized for electrical propulsion and high power payload

Author

De Boissieu, Jean-Baptiste, Bouhours, Gilles, Cresp, Jean-Michel, Boulanger, Bernard, Bourgue, Olivier, Meinguet, Fabien, Bekemans, Marc, Cesaretti, Giovanni, Ghislanzoni, Luca, Inguimbert, Virginie, Taylor, Roger, Gaffinet, Ben, Furno, Ivo, Avino, Fabio, Howling, Alan, Martens, Paul, Nebuloni, Stefano, Bommottet, Daniel, Thales Alenia Space [Cannes], Thales Alenia Space, Thalès Alenia Space (Mont-sur-Marchienne, Belgique), Sitael S.p.a., ONERA / DPHY, Université de Toulouse [Toulouse], ONERA-PRES Université de Toulouse, Ionix Systems, Ecole Polytechnique Fédérale de Lausanne (EPFL), RUAG Space (Nyon, Suisse), and PRES Université de Toulouse-ONERA

Subjects
[PHYS]Physics [physics], HV-EPSA, [SPI]Engineering Sciences [physics], HIGH POWER, PANNEAU SOLAIRE, ELECTRIC PROPULSION, HALL EFFECT THRUSTER, DIRECTDRIVE, HIGH VOLTAGE, SOLAR ARRAY, SATELLITE
Abstract

International audience; There is a large design variety of power buses, with voltage levels typically ranging from 28 to 100V. This state-of-art is well adapted to past and current needs in term of power conditioning and disctribution for science and telecommunication satellites. NEvertheless, a short-term need is rising for higher operating voltages, especially for the new electric propulsion systems and high-power payloads. The currently available solutions are to add DC/DC converters inisde echa user equipement to generate all its necessary internal supply lines for the satellite primary power bus. For high power/high voltage loads, this DC/DC stage leads to power dissipation and lowers the overall efficiency of the power chain. A major step forward would be to increase the voltage directly at the level of the primary bus in order to remove some voltage conversion stages leading to lower mass, cost, volume and power dissipation. The work performed within the European Union H2020 project "HV-EPSA" was aimed to study benefits and impact of the implementation of a bus voltage from 300V to 600V, including solar array, solar array drive mechnism, power conditioning and distribution, Hall effect thruster with direct drive topology, battery and harnesses. The main problematic to solve were arcing at high voltage/low pressure (Paschen law), interaction between plasma (natural and from plasmic propulsion) and solar arrays, and distribution function using GaN mosfet. Several test campaigns were performed and the results are presented in the paper.; Il existe une grande variété de conception de bus d'alimentation, avec des niveaux de tension allant généralement de 28 à 100 V. Cet état de l'art est bien adapté aux besoins passés et actuels en termes de conditionnement et de distribution de puissance pour les satellites scientifiques et de télécommunications. Néanmoins, le besoin à court terme augmente pour des tensions de fonctionnement plus élevées, en particulier pour les nouveaux systèmes de propulsion électrique et les charges utiles à haute puissance. Les solutions actuellement disponibles consistent à ajouter des convertisseurs DC / DC à l'intérieur de chaque équipement utilisateur afin de générer toutes ses lignes d'alimentation interne nécessaires pour le bus d'alimentation primaire du satellite. Pour les charges haute puissance / haute tension, cet étage DC / DC conduit à une dissipation de puissance et diminue l'efficacité globale de la chaîne de puissance. Un grand pas en avant serait d'augmenter la tension directement au niveau du bus primaire afin de supprimer certains étages de conversion de tension conduisant à une diminution de la masse, du coût, du volume et de la dissipation de puissance. Les travaux réalisés dans le cadre du projet H2020 de l'Union européenne "HV-EPSA" visaient à étudier les avantages et l'impact de la mise en œuvre d'une tension de bus de 300V à 600V, y compris les panneaux solaires, les systèmes d'entraînement de panneaux solaires, le conditionnement et la distribution de l'énergie, le propulseur à effet Hall avec topologie à entraînement direct, batterie et cablâge. Les principaux problèmes à résoudre étaient les arcs à haute tension / basse pression (loi de Paschen), l'interaction entre le plasma (naturel et de propulsion plasmique) et les panneaux solaires, et la fonction de distribution à l'aide du mosfet GaN. Plusieurs campagnes de tests ont été réalisées et les résultats sont présentés dans l'article.

Published
2019

36. Entering the plasma agriculture field: An attempt to standardize protocols for plasma treatment of seeds.

Author

Waskow, Alexandra, Avino, Fabio, Howling, Alan, and Furno, Ivo

Subjects
SEED treatment, SEED technology, MEDICAL protocols, AGRICULTURAL technology, AGRICULTURAL processing
Abstract

Plasma treatments are currently being assessed as a seed processing technology for agricultural purposes. There is sufficient information as a proof‐of‐concept, but a lack of standardization in the methodology prevents a convincing evaluation of plasma treatment on seeds. It would be helpful to coordinate research efforts to make the entry for newcomers into this interdisciplinary field less overwhelming and to aid in transferring this technology into the industry by establishing a common protocol. This review presents the parameters used in the seed preparation, the plasma treatment of the seed, and the seed posttreatment. This summary of the plasma and biological parameters is intended to raise awareness about questions that need to be addressed to properly record protocol details and reproduce results for the plasma treatment of seeds. [ABSTRACT FROM AUTHOR]

Published
2022
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37. Magnetic field configurational study on a helicon-based plasma source for future neutral beam systems

Author

Ahmed, Kamal M, primary, Agnello, Riccardo, additional, Béchu, Stéphane, additional, Cartry, Gilles, additional, de Esch, H P L, additional, Furno, Ivo, additional, Guittienne, Philippe, additional, Howling, Alan, additional, Jacquier, Rémy, additional, Morgal, Iaroslav, additional, Sadeghi, Nader, additional, and Simonin, Alain, additional

Published
2019
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38. The RAID Experiment for the Investigation of Negative Ion Physics for Fusion Applications

Author

Furno Ivo, Barbisan Marco, Agnello Riccardo, Pasqualotto Roberto, Howling Alan, Pluyshev Gennady, and Jaquier Rémy

Subjects
basic plasma physics device, Physics::Plasma Physics, helicon plasma, Investigation of Negative Ion Physics, Resonant Antenna Ion Device, Fusion Applications, RAID
Abstract

The Neutral Beam (NB) system for ITER will deliver an ion beam with energy of 1 MeV and current of 40 A. Only NB systems based on negative ions can attain the neutralization efficiency required for the NB system in ITER. Helicon plasmas are a promising candidate for the production of negative ions. The RAID (Resonant Antenna Ion Device) at the Swiss Plasma Center represents a crucial step in understanding helicon plasma physics and negative ions production through volume processes. In this talk the last advances on RAID will be presented including the preliminary measurements of H- density by means of Cavity RingDown Spectroscopy and microwave interferometry measurements.

Published
2017

46. RF inductive probe to measure plasma complex conductivity

Author

Howling, Alan, Guittienne, Philippe, Jacquier, Remy, and Furno, Ivo

Abstract

Invited talk, publication in 2017: Electromagnetic, complex image model of a large area RF resonant antenna as inductive plasma source Ph Guittienne, R Jacquier, A A Howling, and I Furno. Plasma Sources, Sci. Technol. 26, 035010 (2017).

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