| Paper | Title | Other Keywords | Page |
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| TUWZO01 | Measurements of Plasma Parameters Near Resonance Zones and Peripheral Regions in ECRIS | ECR, plasma, ECRIS, electron | 60 |
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We have investigated how to produce multicharged ions efficiently. Recently, we have focused on waves propagations in plasma and conducted the Upper-hybrid Resonance (UHR) experiments. [1] We have also conducted experiments heating by the coaxial semi-dipole antenna to enhance the right-hand polarization wave, which contributes to ECR. [2] Multicharged ion beams have been improved using various means, e.g., the increase of the magnetic field and the microwave frequency, the DC biased plate-tuner, mixing low z gases, and the multiplex frequencies heating. However, the microwave launching position has been empirically determined on conventional ECRIS’s. There is still some room for improvement with the respect to more efficient excitation of the wave propagation. In this research, we estimate the wave propagation near the ECR zone, and in the opposite peripheral region beyond it. We measure plasma parameters in those regions by two Langmuir probes inserted into each location at the same time. In near future, we optimize the microwave-launching in the case of the fundamental frequency for ECR and the second frequency for UHR in order to enhance their incidence to the vacuum chamber.
[1]Y. Kato et al, AIP Conf. Proc. 2011, 020005 (2018). [2]W. Kubo, et al, RSI, 2020, 91, 023317 (2020). |
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Slides TUWZO01 [5.656 MB] | ||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-TUWZO01 | ||
| About • | Received ※ 24 September 2020 — Revised ※ 01 October 2020 — Accepted ※ 03 December 2020 — Issue date ※ 16 February 2022 | ||
| Cite • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| TUZZO06 | Beams with Three-Fold Rotational Symmetry: A Theoretical Study | ECR, ion-source, solenoid, simulation | 110 |
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| Beams from ECR ion sources have 3-fold transverse rotational symmetry induced by the ECR sextupole. The symmetry imposes equality constraints among transverse beam moments, which can be derived using a theoretical framework we developed. Since the constraints are solely a consequence of the rotational symmetry of external fields, they hold for a multi-species beam with arbitrary composition and space charge intensity. These constraints provide a new tool to analyze phase space properties of ECR beams and their impact on low-energy transport. We prove that, regardless of their triangulated spatial density profile, beams with 3-fold rotational symmetry have the same RMS emittance and Twiss parameters along any transverse direction. These counter-intuitive results are applied to the FRIB Front End to show how symmetry arguments challenge long-standing assumptions and bring clarity to the beam dynamics. | |||
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Slides TUZZO06 [0.846 MB] | ||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-TUZZO06 | ||
| About • | Received ※ 28 September 2020 — Revised ※ 14 May 2021 — Accepted ※ 18 May 2021 — Issue date ※ 03 November 2021 | ||
| Cite • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||
| WEZZO01 | Role of the 1+ Beam Optics Upstream the SPIRAL1 Charge Breeder | optics, simulation, plasma, quadrupole | 146 |
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The SPIRAL1 charge breeder (SP1CB) is under opera-tion. Radioactive ion beam (RIB) has already been deliv-ered [1] to Physicist for experiments. Charge breeding efficiencies demonstrated high performances for stable ion beams than RIB’s. The beam optics, prior to the injection of the 1+ ions into the SP1CB, is of prime im-portance [2] for obtaining such high efficiencies. Moreo-ver, the intensities of the RIB’s are so low, and indeed difficult to tune the SP1CB. A stable beam having a close B’ is required to find out the set of optic parameters preceding the tuning of the RIB. Hence, it has been de-cided to focus our effort on the control of 1+ beam optics leading to high charge breeding efficiencies whatever the 1+ mass, energy and Target Ion Source System (TISS) used. This contribution will show the strategy undertaken to overcome that problem and the results obtained.
[1] L. Maunoury et al., Proceedings of the 23th Int. Workshop on ECR Ion Sources, Catania, Italy (2018) [2] A. Annaluru, PhD thesis, Université Caen Normandie (2019) |
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Slides WEZZO01 [4.375 MB] | ||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEZZO01 | ||
| About • | Received ※ 29 September 2020 — Revised ※ 09 October 2020 — Accepted ※ 03 December 2020 — Issue date ※ 21 January 2021 | ||
| Cite • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | ||