ECRIS2024 - List of Keywords (operation)

Paper	Title	Other Keywords	Page
MOC1	Recent achievements in the production of metallic ion beams with the CAPRICE ECRIS at GSI	ECR, ECRIS, plasma, extraction	14
	A. Andreev, F. Maimone, J. Mäder, M. Galonska, R. Lang, R. Hollinger GSI, Darmstadt, Germany
	The GSI CAPRICE Electron Cyclotron Resonance Ion Source (ECRIS) provides highly-charged ion beams for various experiments at GSI, enabling the delivery of continuous wave (CW) metallic ion beams with low material consumption, which is crucial for producing high charge state ion beams from rare or extremely rare isotopes such as ⁴⁸Ca. These metallic beams are produced utilizing the thermal evaporation technique by resistively heated ovens. Due to the research groups’ demand for higher beam intensities, increased ion currents of higher charge states are now necessary from the CAPRICE ECRIS. A test campaign was conducted to establish and improve the production of high charge states of enriched ⁵⁴Cr and ⁵⁵Mn ion beams. During the tests, plasma images were captured using a CCD camera to support the operation and enable real-time monitoring of the material consumption. Additionally, a hot screen was used to protect the ceramic insulators in the extraction system from metal deposition, thereby improving the operational stability of the ECRIS. The application of an optical emission spectroscopy to monitor the stability of metallic ion beams during the operation with the resistively heated ovens was also investigated. This contribution presents the operational experience, the intensities and stability achieved for the aforementioned elements. In addition, an update on a recent improvement involving a specialized oven preparation stand for better conditioning of the ovens is given.
	Slides MOC1 [3.835 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-MOC1
About •	Received ※ 13 December 2024 — Revised ※ 21 January 2025 — Accepted ※ 29 January 2025 — Issued ※ 14 May 2025
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOP10	Light ions from the GTS-LHC ion source for future physics at CERN	emittance, rfq, extraction, experiment	53
	D. Küchler, B.S. Bhaskar, G. Bellodi, M. Slupecki, R. Scrivens CERN, Geneva, Switzerland
	Starting from 2028, physics programmes using ions at CERN have requested lighter ions than the lead usually produced. The Working Group on Future Ions in the CERN Accelerator Complex has been mandated to assess the feasibility of the production and operation of these new ion species. The ion beam production from two of the chosen elements, krypton and magnesium, was studied in the GTS-LHC ion source, and the preliminary results of beam intensity, stability and emittance will be presented, as well as proposed modifications to improve performance.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-MOP10
About •	Received ※ 13 September 2024 — Revised ※ 17 September 2024 — Accepted ※ 29 January 2025 — Issued ※ 05 February 2025
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUD1	Time-resolved measurement of ion beam energy spread variation due to kinetic plasma instabilities in CW and pulsed operation of an ECRIS	plasma, ECR, ECRIS, electron	86
	V. Toivanen, H.A. Koivisto University of Jyväskylä, Jyväskylä, Finland J.O. Huovila University of Eastern Finland, Joensuu, Finland O.A. Tarvainen STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
	The energy spread of ion beams extracted from Electron Cyclotron Resonance (ECR) ion sources is influenced by plasma conditions such as the plasma potential, and effects taking place in the beam formation region. Kinetic plasma instabilities have a significant impact on the plasma properties, and consequently on the ion beam energy spread. We present experimental results of time-resolved energy spread behaviour when kinetic plasma instabilities are present in CW and pulsed operation of the JYFL 14 GHz ECR ion source. It is shown that the instability-induced energy spread variation corresponds to a momentary plasma potential increase up to several kV from the steady-state value of 10–30 V. The method for measuring the time-resolved energy spread variation is presented, and the consequences of the energy spread and the underlying plasma potential variation for ECRIS operation are discussed.
	Slides TUD1 [3.281 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-TUD1
About •	Received ※ 13 September 2024 — Revised ※ 18 September 2024 — Accepted ※ 29 March 2025 — Issued ※ 09 May 2025
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP01	Operation with the LAPECR3 ion sources for cancer therapy accelerators	ion-source, ECR, extraction, high-voltage	91
	J.Q. Li, C. Qian, J.D. Ma, L.T. Sun, X.Z. Zhang, H.W. Zhao, Y. Cao IMP/CAS, Lanzhou, People’s Republic of China H.W. Zhao UCAS, Beijing, People’s Republic of China G. Jin LANITH, Lanzhou, People’s Republic of China
	An all-permanent magnet electron cyclotron resonance ion source-LAPECR3 (Lanzhou All Permanent magnet Electron Cyclotron Resonance ion source No.3) had been developed as the C⁵⁺ ion beam injector of Heavy Ion Medical Machine (HIMM) accelerator facility since 2009 in China. The first HIMM demo facility was built in Wuwei city in 2015, which had been officially licensed to treat patients in early 2020. The facility has been proven to be very effective, and more than 1000 patients have been treated so far. In order to prevent ion source failure, each facility employs two identical LAPECR3 ion sources to supply C⁵⁺ beam. At present, there are eight HIMM facilities under construction or in operation, and more than 16 LAPECR3 ion sources have been built. In order to improve the performance of the ion source for long term operation, some techniques were employed to optimize source performance and to avoid the damage of key equipment. This paper will introduce the operation status of LAPECR ion sources at these HIMM facilities and present the latest results of carbon beam production.
	Poster TUP01 [1.475 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-TUP01
About •	Received ※ 10 September 2024 — Revised ※ 14 September 2024 — Accepted ※ 27 May 2025 — Issued ※ 26 June 2025
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEB2	Applying machine learning techniques to the operation of the superconducting ECR ion source VENUS	ion-source, controls, ECR, plasma	152
	D.S. Todd, A. Kireeff, H. Crawford, J.Y. Benitez, M. Salathe, V. Watson, Y.S. Lai LBNL, Berkeley, CA, USA
	Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Nuclear Physics program under Award Numbers DE-FOA-0002490 and DE-FOA-0002875 An operator of the superconducting ECR ion source VENUS tasked with optimizing the current of a specific ion species or finding a stable operating mode is faced with an operation space composed of ten-to-twenty knobs in which to determine the next move. Machine learning techniques are well-suited to multidimensional optimization spaces. Over the last three years we have been working to employ such techniques with the VENUS ion source. We will present how the introduction of computer control has allowed us to automate tasks such as source baking or to utilize optimization tools to maximize beam currents with no human intervention. Our more recent applications of Bayesian optimization and reinforcement learning to beam current maximization and the maintenance of long term source stability will also be presented. Finally, we will discuss control and diagnostic changes that we have employed to exploit the faster data collection and decision making abilities when VENUS is under computer control.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-WEB2
About •	Received ※ 04 October 2024 — Revised ※ 18 October 2024 — Accepted ※ 26 February 2025 — Issued ※ 24 May 2025
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEB3	Beam intensity prediction using ECR plasma images and machine learning	plasma, ECR, ion-source, extraction	156
	Y. Morita, T. Nishi RIKEN, Saitama, Japan A. Kasagi Rikkyo University, Tokyo, Japan K. Kamakura University of Tokyo, Tokyo, Japan N. Oka National Institute of Information and Communications Technology, Tokyo, Japan
	Long-term beam stability is one of the important issues in supplying multivalent heavy ion beams using an Electron Cyclotron Resonance Ion Source (ECRIS). When the beam intensity drops for long-term operation, the ECRIS parameters need to be tuned to restore the original beam intensity. Continuous measurement of the beam intensity using a Faraday cup (FC) is impractical while the beam is in use. We have had to rely on an unreliable method of monitoring the total drain current to estimate the beam intensity during beamtime. To resolve this issue, we propose a new method for predicting the beam intensity at FC using machine learning. Our approach incorporates plasma images, captured through a hole in the beam extraction electrode, and operating parameters as input data for the machine learning model. In short-term test datasets, our model has successfully produced rough predictions of the beam intensity. This presentation will detail the prediction model and its prediction results on the test data.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-WEB3
About •	Received ※ 14 September 2024 — Revised ※ 18 October 2024 — Accepted ※ 02 February 2025 — Issued ※ 04 March 2025
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOC1

Recent achievements in the production of metallic ion beams with the CAPRICE ECRIS at GSI

ECR, ECRIS, plasma, extraction

14

A. Andreev, F. Maimone, J. Mäder, M. Galonska, R. Lang, R. Hollinger
GSI, Darmstadt, Germany

The GSI CAPRICE Electron Cyclotron Resonance Ion Source (ECRIS) provides highly-charged ion beams for various experiments at GSI, enabling the delivery of continuous wave (CW) metallic ion beams with low material consumption, which is crucial for producing high charge state ion beams from rare or extremely rare isotopes such as ⁴⁸Ca. These metallic beams are produced utilizing the thermal evaporation technique by resistively heated ovens. Due to the research groups’ demand for higher beam intensities, increased ion currents of higher charge states are now necessary from the CAPRICE ECRIS. A test campaign was conducted to establish and improve the production of high charge states of enriched ⁵⁴Cr and ⁵⁵Mn ion beams. During the tests, plasma images were captured using a CCD camera to support the operation and enable real-time monitoring of the material consumption. Additionally, a hot screen was used to protect the ceramic insulators in the extraction system from metal deposition, thereby improving the operational stability of the ECRIS. The application of an optical emission spectroscopy to monitor the stability of metallic ion beams during the operation with the resistively heated ovens was also investigated. This contribution presents the operational experience, the intensities and stability achieved for the aforementioned elements. In addition, an update on a recent improvement involving a specialized oven preparation stand for better conditioning of the ovens is given.

Slides MOC1 [3.835 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-MOC1

About •

Received ※ 13 December 2024 — Revised ※ 21 January 2025 — Accepted ※ 29 January 2025 — Issued ※ 14 May 2025

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOP10

Light ions from the GTS-LHC ion source for future physics at CERN

emittance, rfq, extraction, experiment

53

D. Küchler, B.S. Bhaskar, G. Bellodi, M. Slupecki, R. Scrivens
CERN, Geneva, Switzerland

Starting from 2028, physics programmes using ions at CERN have requested lighter ions than the lead usually produced. The Working Group on Future Ions in the CERN Accelerator Complex has been mandated to assess the feasibility of the production and operation of these new ion species. The ion beam production from two of the chosen elements, krypton and magnesium, was studied in the GTS-LHC ion source, and the preliminary results of beam intensity, stability and emittance will be presented, as well as proposed modifications to improve performance.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-MOP10

About •

Received ※ 13 September 2024 — Revised ※ 17 September 2024 — Accepted ※ 29 January 2025 — Issued ※ 05 February 2025

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUD1

Time-resolved measurement of ion beam energy spread variation due to kinetic plasma instabilities in CW and pulsed operation of an ECRIS

plasma, ECR, ECRIS, electron

86

V. Toivanen, H.A. Koivisto
University of Jyväskylä, Jyväskylä, Finland
J.O. Huovila
University of Eastern Finland, Joensuu, Finland
O.A. Tarvainen
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom

The energy spread of ion beams extracted from Electron Cyclotron Resonance (ECR) ion sources is influenced by plasma conditions such as the plasma potential, and effects taking place in the beam formation region. Kinetic plasma instabilities have a significant impact on the plasma properties, and consequently on the ion beam energy spread. We present experimental results of time-resolved energy spread behaviour when kinetic plasma instabilities are present in CW and pulsed operation of the JYFL 14 GHz ECR ion source. It is shown that the instability-induced energy spread variation corresponds to a momentary plasma potential increase up to several kV from the steady-state value of 10–30 V. The method for measuring the time-resolved energy spread variation is presented, and the consequences of the energy spread and the underlying plasma potential variation for ECRIS operation are discussed.

Slides TUD1 [3.281 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-TUD1

About •

Received ※ 13 September 2024 — Revised ※ 18 September 2024 — Accepted ※ 29 March 2025 — Issued ※ 09 May 2025

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP01

Operation with the LAPECR3 ion sources for cancer therapy accelerators

ion-source, ECR, extraction, high-voltage

91

J.Q. Li, C. Qian, J.D. Ma, L.T. Sun, X.Z. Zhang, H.W. Zhao, Y. Cao
IMP/CAS, Lanzhou, People’s Republic of China
H.W. Zhao
UCAS, Beijing, People’s Republic of China
G. Jin
LANITH, Lanzhou, People’s Republic of China

An all-permanent magnet electron cyclotron resonance ion source-LAPECR3 (Lanzhou All Permanent magnet Electron Cyclotron Resonance ion source No.3) had been developed as the C⁵⁺ ion beam injector of Heavy Ion Medical Machine (HIMM) accelerator facility since 2009 in China. The first HIMM demo facility was built in Wuwei city in 2015, which had been officially licensed to treat patients in early 2020. The facility has been proven to be very effective, and more than 1000 patients have been treated so far. In order to prevent ion source failure, each facility employs two identical LAPECR3 ion sources to supply C⁵⁺ beam. At present, there are eight HIMM facilities under construction or in operation, and more than 16 LAPECR3 ion sources have been built. In order to improve the performance of the ion source for long term operation, some techniques were employed to optimize source performance and to avoid the damage of key equipment. This paper will introduce the operation status of LAPECR ion sources at these HIMM facilities and present the latest results of carbon beam production.

Poster TUP01 [1.475 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-TUP01

About •

Received ※ 10 September 2024 — Revised ※ 14 September 2024 — Accepted ※ 27 May 2025 — Issued ※ 26 June 2025

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEB2

Applying machine learning techniques to the operation of the superconducting ECR ion source VENUS

ion-source, controls, ECR, plasma

152

D.S. Todd, A. Kireeff, H. Crawford, J.Y. Benitez, M. Salathe, V. Watson, Y.S. Lai
LBNL, Berkeley, CA, USA

Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Nuclear Physics program under Award Numbers DE-FOA-0002490 and DE-FOA-0002875
An operator of the superconducting ECR ion source VENUS tasked with optimizing the current of a specific ion species or finding a stable operating mode is faced with an operation space composed of ten-to-twenty knobs in which to determine the next move. Machine learning techniques are well-suited to multidimensional optimization spaces. Over the last three years we have been working to employ such techniques with the VENUS ion source. We will present how the introduction of computer control has allowed us to automate tasks such as source baking or to utilize optimization tools to maximize beam currents with no human intervention. Our more recent applications of Bayesian optimization and reinforcement learning to beam current maximization and the maintenance of long term source stability will also be presented. Finally, we will discuss control and diagnostic changes that we have employed to exploit the faster data collection and decision making abilities when VENUS is under computer control.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-WEB2

About •

Received ※ 04 October 2024 — Revised ※ 18 October 2024 — Accepted ※ 26 February 2025 — Issued ※ 24 May 2025

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEB3

Beam intensity prediction using ECR plasma images and machine learning

plasma, ECR, ion-source, extraction

156

Y. Morita, T. Nishi
RIKEN, Saitama, Japan
A. Kasagi
Rikkyo University, Tokyo, Japan
K. Kamakura
University of Tokyo, Tokyo, Japan
N. Oka
National Institute of Information and Communications Technology, Tokyo, Japan

Long-term beam stability is one of the important issues in supplying multivalent heavy ion beams using an Electron Cyclotron Resonance Ion Source (ECRIS). When the beam intensity drops for long-term operation, the ECRIS parameters need to be tuned to restore the original beam intensity. Continuous measurement of the beam intensity using a Faraday cup (FC) is impractical while the beam is in use. We have had to rely on an unreliable method of monitoring the total drain current to estimate the beam intensity during beamtime. To resolve this issue, we propose a new method for predicting the beam intensity at FC using machine learning. Our approach incorporates plasma images, captured through a hole in the beam extraction electrode, and operating parameters as input data for the machine learning model. In short-term test datasets, our model has successfully produced rough predictions of the beam intensity. This presentation will detail the prediction model and its prediction results on the test data.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-WEB3

About •

Received ※ 14 September 2024 — Revised ※ 18 October 2024 — Accepted ※ 02 February 2025 — Issued ※ 04 March 2025

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)