A4 Article in conference proceedings
Beam Formation Studies on the CERN IS03b H Source (2022)

Lettry, J., Vnuchenko, A., Bertolo, S., Mastrostefano, C., O’Neil, M., di Lorenzo, F., Coutron, Y., Steyeart, D., Riffaud, B., Thiboud, J., Guida, R., Kapusniak, K., Charvet, C., Teissandier, B., Moyret, P., Roncarolo, F., Bart Pedersen, S., Duraffourg, M., Vuitton, C., . . . Revel, A. (2022). Beam Formation Studies on the CERN IS03b H Source. In ICIS2021 : 19th International Conference on Ion Sources (Article 012036). IOP Publishing. Journal of Physics : Conference Series, 2244. https://doi.org/10.1088/1742-6596/2244/1/012036

JYU authors or editors

Publication details

All authors or editors: Lettry, J.; Vnuchenko, A.; Bertolo, S.; Mastrostefano, C.; O’Neil, M.; di Lorenzo, F.; Coutron, Y.; Steyeart, D.; Riffaud, B.; Thiboud, J.; et al.

Parent publication: ICIS2021 : 19th International Conference on Ion Sources

Conference:

Place and date of conference: Online, 20.-24.9.2021

Journal or series: Journal of Physics : Conference Series

ISSN: 1742-6588

eISSN: 1742-6596

Publication year: 2022

Publication date: 01/04/2022

Number in series: 2244

Article number: 012036

Publisher: IOP Publishing

Publication country: United Kingdom

Publication language: English

DOI: https://doi.org/10.1088/1742-6596/2244/1/012036

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/82374

Abstract

An H- ion source is being operated at the new 160 MeV linear injector (Linac4) of the CERN accelerator complex. The source's plasma is of the Radio Frequency Inductively Coupled Plasma type (RF-ICP), without magnetic cusp and runs with Cs-loss compensation [1]. Vertical downward oriented filter- and electron dump-dipolar magnetic fields expand over the plasma chamber, beam-formation, beam-extraction and electron dump regions and generate horizontal asymmetry and beam angular deflection partially compensated by mechanical alignment of the front-end. The H- beam is generated via volume and caesiated plasma surface modes, the latter inducing a radial asymmetry characterized by an increased current density close to the plasma electrode surface [2]. Asymmetries affecting the meniscus shape, or its current density have to be simulated via 3D Particle In Cell Monte Carlo (PIC-MC) solvers, such as the Orsay Negative Ion eXtraction code (ONIX) [3]. Validation of these simulations require dedicated measurements. This contribution describes experimental methods newly implemented at CERN's ion source test stand and initial results for Optical and Beam Emission Spectroscopy (OES, BES), emittance and beam profile measurements. In a later stage, the gathered data sets can be compared to source plasma parameters and extracted beam parameters from PIC-MC simulations, once coupled to the Ion Beam Simulation (IBSimu) [4] beam transport code. The experimental parameter space includes RF-power, density of neutrals, position of the RF coil and extraction field. Beams of H-, D- and protons were produced; examples of measured data are presented in this contribution.

Keywords: plasma physics; particle accelerators

Contributing organizations

Ministry reporting: Yes

Reporting Year: 2022

JUFO rating: 1