ECRIS2024 - List of Keywords (electron)

Paper	Title	Other Keywords	Page
MOC2	A novel inductive oven design for the production of high current, metal ion beams	plasma, cyclotron, ion-source, target	19
	D.S. Todd, J.Y. Benitez LBNL, Berkeley, CA, USA
	Essential to the proposed search for element 120 at LBNL’s 88-Inch Cyclotron is the continual delivery of over a particle microamp of ⁵⁰Ti¹²⁺ for weeks-long campaigns spanning many months. The fully-superconducting ECR ion source VENUS will be the injector source for these runs, and we have developed a new inductive oven design that can survive VENUS’ high magnetic fields while injecting metallic gas into the plasma with high efficiency. The new oven employs a vertical susceptor to permit use with metals that melt before outgassing sufficiently, while also allowing a rotation of the oven’s material exit toward the plasma center for better conversion efficiency to the produced beam. The performance of VENUS with this oven has been outstanding: as reported here, 282 MeV ⁵⁰Ti¹²⁺ beams with stable currents between 1.0 and 1.5 pμA have been delivered for superheavy element searches over multiple ten-day runs.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-MOC2
About •	Received ※ 04 October 2024 — Revised ※ 10 October 2024 — Accepted ※ 29 January 2025 — Issued ※ 22 June 2025
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOD1	Development of deuterium-deuterium compact neutron source	plasma, target, neutron, vacuum	23
	A. Pérez, I. Arredondo, J. Portilla, V. Etxebarria University of the Basque Country, Faculty of Science and Technology, Bilbao, Spain A. Roldán, J. Praena UGR, Granada, Spain J. Feuchtwanger Ikerbasque, Bilbao, Spain
	In the present work, we will present the status of the deuterium-deuterium (D-D) neutron source that is being developed in collaboration between the University of Granada and the University of the Basque Country (Spain). Our neutron source consists of an ECR ion source which accelerates a deuteron beam towards a deuterated target. The ionization to achieve the deuterium plasma is achieved by radiating the cylindrical ERC plasma chamber with a magnetron 2.45 GHz signal and an 875 G magnetic field generated by 6 NdFeB magnets located around the plasma chamber. Moreover, a cylindrical alumina RF window is used to keep the vacuum status from the ambient pressure condition inside the WR340 and helping the plasma to ignite. Once the plasma is generated, the deuterons are extracted from the plasma chamber using a Pierce electrode geometry and three other electrostatic lenses, fixed to different negative potentials. The beam is accelerated towards copper target disk with a deuterated titanium mesh fixed to -100 kV which generates the desired neutron radiation. There are several applications of D-D neutron sources across scientific and industrial domains. In case of University of Granada and its deep relation with IFMIF-DONES neutron source, it is worthy to mention that we plan to carry out experiments for determining the cross-sections of relevant isotopes in the studies of IFMIF-DONES to a better simulation of the behaviour of such material under high neutron flux irradiation.
	Slides MOD1 [9.890 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-MOD1
About •	Received ※ 14 September 2024 — Revised ※ 17 September 2024 — Accepted ※ 29 January 2025 — Issued ※ 21 June 2025
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOP01	Characterization of the 2.45 GHz DREEBIT ECRIS via optical spectroscopy	plasma, ECR, ECRIS, ion-source	31
	M. Molodtsova, A. Philipp, E. Ritter DREEBIT, Großröhrsdorf, Germany
	ECR ion sources are widely used to provide ions for various experimental setups. DREEBIT GmbH aims to industrialize this type of ion source technology for efficient and reliable use in, e. g., hadron cancer therapy as well as ion implantation of semiconductors. Our goal is to build table-top sized ion sources which can easily be handled as part of a larger machine such as a particle accelerator or target irradiation facility, thereby fulfilling high requirements on beam current, quality, stability as well as reproducibility in serial production. To achieve this, we have already optimized the microwave injection system and magnetic plasma confinement by introducing a simple method to allow for injection of circularly polarized waves and adjusted the magnetic field distribution which led to an 80 % increase of beam current. In the present work, we show how optical emission spectroscopy was used to gain deeper information about the plasma of this specific type of ion source, independent from its ion extraction system. The plasma characterization includes studies of the electron energy distribution and the density of atomic and molecular hydrogen showing that the previous design changes of introducing circularly polarized microwaves and optimizing the magnetic field distribution have led to a well-optimized ECR ion source concerning plasma heating and proton production inside the plasma, indicating how the source performance can be enhanced in further steps.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-MOP01
About •	Received ※ 02 October 2024 — Revised ※ 09 October 2024 — Accepted ※ 29 January 2025 — Issued ※ 07 April 2025
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MOP04	ALISES v3 ion source in various configuration along the year	ion-source, extraction, plasma, proton	39
	O. Tuske, A. Dubois, O. Delferrière, Y. Gauthier, Y. Sauce CEA-IRFU, Gif-sur-Yvette, France
	ALISESv3 is a very compact light ion source that has been developed at CEA Saclay in 2018. The easy maintenance procedure of this source allowed us to test many different configurations. On the BETSI test bench equipped with an single Alisson Scanner and a pair a solenoid/deviator, we studied the extraction energy influence, we changed the number of electrodes in order to extract different kind of ions other than protons. This paper will describe briefly the ALISES 3 ion source and will present some results that we gathered in a year.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-MOP04
About •	Received ※ 13 September 2024 — Revised ※ 04 February 2025 — Accepted ※ 06 February 2025 — Issued ※ 07 May 2025
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUB1	Progress in 3D self-consistent full wave-PIC modelling of space resolved ECR plasma properties	plasma, ECR, simulation, ECRIS	76
	A. Pidatella, G.S. Mauro, B. Mishra, E. Naselli, G. Torrisi, D. Mascali INFN-LNS, Catania, Italy A. Galatà, C.S. Gallo INFN-LNL, Legnaro (PD), Italy
	We present updates of a simulation suite to model in-plasma ion-electron dynamics, including self-consistent electromagnetic (EM) wave propagation and ion population kinetics to study atomic processes in ECR plasmas. The EM absorption is modelled by a heuristic collisional term in the cold dielectric tensor. However, we are stepping beyond the cold approximation, modelling the hot tensor with non-collisional RF wave damping. The tool calculates steady-state particle distributions via a full wave-PIC code and solves for collisional-radiative process giving atomic population and charge state distribution. The scheme is general and applicable to many physics’ cases of interest for the ECRIS community, including the build-up of the charge-state-distribution and the plasma emitted X-ray and optical radiation. We present its last updates and future perspectives, using as a case-study the PANDORA scenario. We report about studying in-plasma dynamics of injected metallic species and radioisotopes ionisation efficiency for different injection conditions and plasma parameters. The code is capable of reconstructing space-resolved plasma emissivity, to be directly compared to plasma emission measurements, and modelling plasma-induced modification of radioactivity.
	Slides TUB1 [21.575 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-TUB1
About •	Received ※ 03 October 2024 — Revised ※ 14 October 2024 — Accepted ※ 29 January 2025 — Issued ※ 01 May 2025
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUB2	Simulation of surface X-ray emission from the ASTERICS ECR ion source	extraction, plasma, ion-source, injection	81
	T. Thuillier, A. Cernuschi, B. Cheymol, M. Kasulja, E. Lagorio, C. Peaucelle, F. Vezzu LPSC, Grenoble Cedex, France M. Dubois, F. Lemagnen GANIL, Caen, France T. Cadoux, H. Felice, D. Simon CEA-IRFU, Gif-sur-Yvette, France
	A new electron cyclotron resonance ion source (ECRIS) named ASTERICS is under development for the NEWGAIN project, aiming at building a new injector for the SPIRAL2 accelerator at GANIL. A Monte Carlo code dedicated to the electron dynamics in ECRIS is used to investigate the local energy, position and velocity distribution of electrons impinging on the plasma chamber wall of ASTERICS. These quantities are presented for both the injection and extraction planes and the radial chamber wall. Results show that the electron energy distribution function is different on each of these three surfaces and that the electron velocity direction to the walls is deeply anisotropic. This data is next used as an input in a Fluka 3-dimensional model including the ASTERICS ECRIS mechanics, a simplified low energy beam line and the experimental cave in which the ion source will be installed. The x-ray flux characteristics around the source are presented. The shielding thickness and its location are studied to grant the safe passage of personnel around the ECRIS location in the accelerator building.
	Slides TUB2 [7.367 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-TUB2
About •	Received ※ 30 October 2024 — Revised ※ 31 October 2024 — Accepted ※ 29 January 2025 — Issued ※ 25 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, operation	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
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TUP04	Tests of a low-energy pepperpot based on a micro-channel plate for high current protons sources 4D-emittance characterization	emittance, proton, ion-source, MMI	94
	A. Thézé, B. Bolzon, A. Dubois, G. Ferrand, O. Tuske CEA-IRFU, Gif-sur-Yvette, France
	In the scope of high current protons sources characterization, the CEA is working on a 4D-emittancemeter based on the pepperpot technology. After some unsuccessful developments with phosphorous scintillators, we decided to test micro-channel plates (MCP) for measurements of proton beams at very low energy (typically between 50 and 100 keV). MCP are supposed to resist to proton beams at very low energy better than scintillators. This work presents some results for MCPs with an ALISES source on the BETSI test bench.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-TUP04
About •	Received ※ 10 September 2024 — Revised ※ 13 September 2024 — Accepted ※ 30 January 2025 — Issued ※ 23 February 2025
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TUP05	RF and multipactor simulations in the plasma chamber of the SILHI proton source	multipactoring, simulation, cavity, ECR	97
	M. Barant, A. Dubois, G. Ferrand, J. Plouin, O. Tuske CEA-IRFU, Gif-sur-Yvette, France
	In the scope of high current protons sources simulations, we tried to simulate the plasma chamber of the SILHI proton source with HFSS. This work focuses on the RF and multipactor simulation close to the boron nitride window.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-TUP05
About •	Received ※ 09 September 2024 — Revised ※ 19 September 2024 — Accepted ※ 30 January 2025 — Issued ※ 27 February 2025
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TUP06	Wien Filter upgrade and measurement for BETSI test bench	proton, ion-source, diagnostics, ECR	101
	O. Tuske, O. Delferrière, Y. Gauthier, Y. Sauce, A. Dubois CEA-IRFU, Gif-sur-Yvette, France
	During first operation of SILHI in 1995 at CEA Saclay, a velocity filter diagnostic (Wien Filter) was installed on the LEBT, analyzing the 100 mA of protons at 95 keV. The device was used many years providing beam proportion measurements on the beam axis. Unfortunately, it was damaged while handling and was no longer working as intended. This paper describes the maintenance and upgrade of the diagnostic as well as the first beam proportion figures with ALISES 2 and ALISES 3 ion sources.
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-TUP06
About •	Received ※ 13 September 2024 — Revised ※ 20 November 2024 — Accepted ※ 04 February 2025 — Issued ※ 06 June 2025
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WEA3	A plasma based, charge state stripper for heavy ion accelerators	plasma, heavy-ion, target, experiment	144
	G.O. Rodrigues IUAC, New Delhi, India
	The ionization of ions to a higher charge state is of central importance for the development of new Accelerator Facilities like FAIR [1], and the resulting cost savings. Currently, mainly gas and foil strippers are used for increasing the charge state even after using a high performance ECR ion source in a typical Accelerator chain. Even when the foil or/and gas stripper efficiency or lifetime has proved to be less than optimal, as these alternatives either require great effort or are practically not suitable for smooth operation in the long term. Free electrons in highly ionized plasmas [2,3] can be effectively used for improving the charge state of heavy ions as the rates of radiative recombination of free electrons are much smaller than those of electron capture on bound electrons, which leads to a substantial increase of the effective charge in a plasma compared to a cold-gas target of the same element. Theta and Z pinch plasmas are possible options which have been explored and experimentally studied at IAP, Frankfurt, Germany [4]. Typical electron line densities required to be achieved are in the range of 10¹⁶ to 10¹⁹ cm⁻³ and electron temperatures of the order of few tens of eV are found to be very favourable as per modelling with the FLYCHK code [5], but also extremely challenging. Such a plasma device, the challenges to be overcome, together with their design details will be presented. [1] https://fair-center.eu/ [2] E. Nardi and Z. Zinamon, Phys. Rev. Lett., vol. 49, p. 1251, 1982. [3] T. Peter and J. Meyer-ter-Vehn, “Energy loss of heavy ions in dense plasma. II. Nonequilibrium charge states and stopping powers”, Phys. Rev. A, vol. 43, pp. 2015–2030, 1991. doi:10.1103/PhysRevA.43.2015 [4] C. Teske, J. Jacoby, F. Senzel, W. Schweizer, Phys. Plasmas, vol. 17, p. 043501, 2010. [5] FLYCHK code: www-amdis.iaea.org
	Slides WEA3 [5.462 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-WEA3
About •	Received ※ 28 March 2025 — Revised ※ 26 May 2025 — Accepted ※ 29 June 2025 — Issued ※ 30 June 2025
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THA2	Numerical design of an innovative superconducting magnetic trap for probing β-decay in ECR plasmas	plasma, injection, ECR, detector	159
	G.S. Mauro, L. Celona, G. Torrisi, A. Pidatella, E. Naselli, F. Russo, B. Mishra, G. Finocchiaro, D. Santonocito, D. Mascali INFN-LNS, Catania, Italy A. Galatà INFN-LNL, Legnaro (PD), Italy
	The main aim of Plasmas for Astrophysics Nuclear Decays Observation and Radiation for Archaeometry (PANDORA) project is to build a flexible magnetic plasma trap where plasma reaches a density nₑ ∼ 10¹¹ – 10¹³ cm⁻³, and a temperature, in units of kT, kTₑ ∼ 0.1 – 30 keV in order to measure, for the first time, nuclear β-decay rates in stellar-like conditions. Here we present the numerical design of the PANDORA magnetic system, carried out by using the commercial simulators OPERA and CST Studio Suite. In particular, we discuss the design choices taken to: 1) obtain the required magnetic field levels at relevant axial and radial positions; 2) avoid the magnetic branches along the plasma chamber wall; 3) find the optimal position for the set of plasma diagnostics that will be employed. The magnetic trap has been conceived to be as large as possible, both in radial and axial directions, in order to exploit the plasma confinement mechanism on a bigger plasmoid volume. The plasma chamber will have a length of 700 mm and a diameter of 280 mm. The magnetic trap tender procedure has been completed in June 2024 and the structure realization is expected to start in late 2024.
	Slides THA2 [6.420 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-THA2
About •	Received ※ 25 January 2025 — Revised ※ 28 January 2025 — Accepted ※ 30 January 2025 — Issued ※ 15 June 2025
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Paper

Title

Other Keywords

Page

MOC2

A novel inductive oven design for the production of high current, metal ion beams

plasma, cyclotron, ion-source, target

19

D.S. Todd, J.Y. Benitez
LBNL, Berkeley, CA, USA

Essential to the proposed search for element 120 at LBNL’s 88-Inch Cyclotron is the continual delivery of over a particle microamp of ⁵⁰Ti¹²⁺ for weeks-long campaigns spanning many months. The fully-superconducting ECR ion source VENUS will be the injector source for these runs, and we have developed a new inductive oven design that can survive VENUS’ high magnetic fields while injecting metallic gas into the plasma with high efficiency. The new oven employs a vertical susceptor to permit use with metals that melt before outgassing sufficiently, while also allowing a rotation of the oven’s material exit toward the plasma center for better conversion efficiency to the produced beam. The performance of VENUS with this oven has been outstanding: as reported here, 282 MeV ⁵⁰Ti¹²⁺ beams with stable currents between 1.0 and 1.5 pμA have been delivered for superheavy element searches over multiple ten-day runs.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-MOC2

About •

Received ※ 04 October 2024 — Revised ※ 10 October 2024 — Accepted ※ 29 January 2025 — Issued ※ 22 June 2025

Cite •

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

MOD1

Development of deuterium-deuterium compact neutron source

plasma, target, neutron, vacuum

23

A. Pérez, I. Arredondo, J. Portilla, V. Etxebarria
University of the Basque Country, Faculty of Science and Technology, Bilbao, Spain
A. Roldán, J. Praena
UGR, Granada, Spain
J. Feuchtwanger
Ikerbasque, Bilbao, Spain

In the present work, we will present the status of the deuterium-deuterium (D-D) neutron source that is being developed in collaboration between the University of Granada and the University of the Basque Country (Spain). Our neutron source consists of an ECR ion source which accelerates a deuteron beam towards a deuterated target. The ionization to achieve the deuterium plasma is achieved by radiating the cylindrical ERC plasma chamber with a magnetron 2.45 GHz signal and an 875 G magnetic field generated by 6 NdFeB magnets located around the plasma chamber. Moreover, a cylindrical alumina RF window is used to keep the vacuum status from the ambient pressure condition inside the WR340 and helping the plasma to ignite. Once the plasma is generated, the deuterons are extracted from the plasma chamber using a Pierce electrode geometry and three other electrostatic lenses, fixed to different negative potentials. The beam is accelerated towards copper target disk with a deuterated titanium mesh fixed to -100 kV which generates the desired neutron radiation. There are several applications of D-D neutron sources across scientific and industrial domains. In case of University of Granada and its deep relation with IFMIF-DONES neutron source, it is worthy to mention that we plan to carry out experiments for determining the cross-sections of relevant isotopes in the studies of IFMIF-DONES to a better simulation of the behaviour of such material under high neutron flux irradiation.

Slides MOD1 [9.890 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-MOD1

About •

Received ※ 14 September 2024 — Revised ※ 17 September 2024 — Accepted ※ 29 January 2025 — Issued ※ 21 June 2025

Cite •

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

MOP01

Characterization of the 2.45 GHz DREEBIT ECRIS via optical spectroscopy

plasma, ECR, ECRIS, ion-source

31

M. Molodtsova, A. Philipp, E. Ritter
DREEBIT, Großröhrsdorf, Germany

ECR ion sources are widely used to provide ions for various experimental setups. DREEBIT GmbH aims to industrialize this type of ion source technology for efficient and reliable use in, e. g., hadron cancer therapy as well as ion implantation of semiconductors. Our goal is to build table-top sized ion sources which can easily be handled as part of a larger machine such as a particle accelerator or target irradiation facility, thereby fulfilling high requirements on beam current, quality, stability as well as reproducibility in serial production. To achieve this, we have already optimized the microwave injection system and magnetic plasma confinement by introducing a simple method to allow for injection of circularly polarized waves and adjusted the magnetic field distribution which led to an 80 % increase of beam current. In the present work, we show how optical emission spectroscopy was used to gain deeper information about the plasma of this specific type of ion source, independent from its ion extraction system. The plasma characterization includes studies of the electron energy distribution and the density of atomic and molecular hydrogen showing that the previous design changes of introducing circularly polarized microwaves and optimizing the magnetic field distribution have led to a well-optimized ECR ion source concerning plasma heating and proton production inside the plasma, indicating how the source performance can be enhanced in further steps.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-MOP01

About •

Received ※ 02 October 2024 — Revised ※ 09 October 2024 — Accepted ※ 29 January 2025 — Issued ※ 07 April 2025

Cite •

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

MOP04

ALISES v3 ion source in various configuration along the year

ion-source, extraction, plasma, proton

39

O. Tuske, A. Dubois, O. Delferrière, Y. Gauthier, Y. Sauce
CEA-IRFU, Gif-sur-Yvette, France

ALISESv3 is a very compact light ion source that has been developed at CEA Saclay in 2018. The easy maintenance procedure of this source allowed us to test many different configurations. On the BETSI test bench equipped with an single Alisson Scanner and a pair a solenoid/deviator, we studied the extraction energy influence, we changed the number of electrodes in order to extract different kind of ions other than protons. This paper will describe briefly the ALISES 3 ion source and will present some results that we gathered in a year.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-MOP04

About •

Received ※ 13 September 2024 — Revised ※ 04 February 2025 — Accepted ※ 06 February 2025 — Issued ※ 07 May 2025

Cite •

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

TUB1

Progress in 3D self-consistent full wave-PIC modelling of space resolved ECR plasma properties

plasma, ECR, simulation, ECRIS

76

A. Pidatella, G.S. Mauro, B. Mishra, E. Naselli, G. Torrisi, D. Mascali
INFN-LNS, Catania, Italy
A. Galatà, C.S. Gallo
INFN-LNL, Legnaro (PD), Italy

We present updates of a simulation suite to model in-plasma ion-electron dynamics, including self-consistent electromagnetic (EM) wave propagation and ion population kinetics to study atomic processes in ECR plasmas. The EM absorption is modelled by a heuristic collisional term in the cold dielectric tensor. However, we are stepping beyond the cold approximation, modelling the hot tensor with non-collisional RF wave damping. The tool calculates steady-state particle distributions via a full wave-PIC code and solves for collisional-radiative process giving atomic population and charge state distribution. The scheme is general and applicable to many physics’ cases of interest for the ECRIS community, including the build-up of the charge-state-distribution and the plasma emitted X-ray and optical radiation. We present its last updates and future perspectives, using as a case-study the PANDORA scenario. We report about studying in-plasma dynamics of injected metallic species and radioisotopes ionisation efficiency for different injection conditions and plasma parameters. The code is capable of reconstructing space-resolved plasma emissivity, to be directly compared to plasma emission measurements, and modelling plasma-induced modification of radioactivity.

Slides TUB1 [21.575 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-TUB1

About •

Received ※ 03 October 2024 — Revised ※ 14 October 2024 — Accepted ※ 29 January 2025 — Issued ※ 01 May 2025

Cite •

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

TUB2

Simulation of surface X-ray emission from the ASTERICS ECR ion source

extraction, plasma, ion-source, injection

81

T. Thuillier, A. Cernuschi, B. Cheymol, M. Kasulja, E. Lagorio, C. Peaucelle, F. Vezzu
LPSC, Grenoble Cedex, France
M. Dubois, F. Lemagnen
GANIL, Caen, France
T. Cadoux, H. Felice, D. Simon
CEA-IRFU, Gif-sur-Yvette, France

A new electron cyclotron resonance ion source (ECRIS) named ASTERICS is under development for the NEWGAIN project, aiming at building a new injector for the SPIRAL2 accelerator at GANIL. A Monte Carlo code dedicated to the electron dynamics in ECRIS is used to investigate the local energy, position and velocity distribution of electrons impinging on the plasma chamber wall of ASTERICS. These quantities are presented for both the injection and extraction planes and the radial chamber wall. Results show that the electron energy distribution function is different on each of these three surfaces and that the electron velocity direction to the walls is deeply anisotropic. This data is next used as an input in a Fluka 3-dimensional model including the ASTERICS ECRIS mechanics, a simplified low energy beam line and the experimental cave in which the ion source will be installed. The x-ray flux characteristics around the source are presented. The shielding thickness and its location are studied to grant the safe passage of personnel around the ECRIS location in the accelerator building.

Slides TUB2 [7.367 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-TUB2

About •

Received ※ 30 October 2024 — Revised ※ 31 October 2024 — Accepted ※ 29 January 2025 — Issued ※ 25 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, operation

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

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TUP04

Tests of a low-energy pepperpot based on a micro-channel plate for high current protons sources 4D-emittance characterization

emittance, proton, ion-source, MMI

94

A. Thézé, B. Bolzon, A. Dubois, G. Ferrand, O. Tuske
CEA-IRFU, Gif-sur-Yvette, France

In the scope of high current protons sources characterization, the CEA is working on a 4D-emittancemeter based on the pepperpot technology. After some unsuccessful developments with phosphorous scintillators, we decided to test micro-channel plates (MCP) for measurements of proton beams at very low energy (typically between 50 and 100 keV). MCP are supposed to resist to proton beams at very low energy better than scintillators. This work presents some results for MCPs with an ALISES source on the BETSI test bench.

DOI •

reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-TUP04

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Received ※ 10 September 2024 — Revised ※ 13 September 2024 — Accepted ※ 30 January 2025 — Issued ※ 23 February 2025

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TUP05

RF and multipactor simulations in the plasma chamber of the SILHI proton source

multipactoring, simulation, cavity, ECR

97

M. Barant, A. Dubois, G. Ferrand, J. Plouin, O. Tuske
CEA-IRFU, Gif-sur-Yvette, France

In the scope of high current protons sources simulations, we tried to simulate the plasma chamber of the SILHI proton source with HFSS. This work focuses on the RF and multipactor simulation close to the boron nitride window.

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reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-TUP05

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Received ※ 09 September 2024 — Revised ※ 19 September 2024 — Accepted ※ 30 January 2025 — Issued ※ 27 February 2025

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TUP06

Wien Filter upgrade and measurement for BETSI test bench

proton, ion-source, diagnostics, ECR

101

O. Tuske, O. Delferrière, Y. Gauthier, Y. Sauce, A. Dubois
CEA-IRFU, Gif-sur-Yvette, France

During first operation of SILHI in 1995 at CEA Saclay, a velocity filter diagnostic (Wien Filter) was installed on the LEBT, analyzing the 100 mA of protons at 95 keV. The device was used many years providing beam proportion measurements on the beam axis. Unfortunately, it was damaged while handling and was no longer working as intended. This paper describes the maintenance and upgrade of the diagnostic as well as the first beam proportion figures with ALISES 2 and ALISES 3 ion sources.

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reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-TUP06

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Received ※ 13 September 2024 — Revised ※ 20 November 2024 — Accepted ※ 04 February 2025 — Issued ※ 06 June 2025

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WEA3

A plasma based, charge state stripper for heavy ion accelerators

plasma, heavy-ion, target, experiment

144

G.O. Rodrigues
IUAC, New Delhi, India

The ionization of ions to a higher charge state is of central importance for the development of new Accelerator Facilities like FAIR [1], and the resulting cost savings. Currently, mainly gas and foil strippers are used for increasing the charge state even after using a high performance ECR ion source in a typical Accelerator chain. Even when the foil or/and gas stripper efficiency or lifetime has proved to be less than optimal, as these alternatives either require great effort or are practically not suitable for smooth operation in the long term. Free electrons in highly ionized plasmas [2,3] can be effectively used for improving the charge state of heavy ions as the rates of radiative recombination of free electrons are much smaller than those of electron capture on bound electrons, which leads to a substantial increase of the effective charge in a plasma compared to a cold-gas target of the same element. Theta and Z pinch plasmas are possible options which have been explored and experimentally studied at IAP, Frankfurt, Germany [4]. Typical electron line densities required to be achieved are in the range of 10¹⁶ to 10¹⁹ cm⁻³ and electron temperatures of the order of few tens of eV are found to be very favourable as per modelling with the FLYCHK code [5], but also extremely challenging. Such a plasma device, the challenges to be overcome, together with their design details will be presented.
[1] https://fair-center.eu/
[2] E. Nardi and Z. Zinamon, Phys. Rev. Lett., vol. 49, p. 1251, 1982.
[3] T. Peter and J. Meyer-ter-Vehn, “Energy loss of heavy ions in dense plasma. II. Nonequilibrium charge states and stopping powers”, Phys. Rev. A, vol. 43, pp. 2015–2030, 1991. doi:10.1103/PhysRevA.43.2015
[4] C. Teske, J. Jacoby, F. Senzel, W. Schweizer, Phys. Plasmas, vol. 17, p. 043501, 2010.
[5] FLYCHK code: www-amdis.iaea.org

Slides WEA3 [5.462 MB]

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reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-WEA3

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Received ※ 28 March 2025 — Revised ※ 26 May 2025 — Accepted ※ 29 June 2025 — Issued ※ 30 June 2025

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THA2

Numerical design of an innovative superconducting magnetic trap for probing β-decay in ECR plasmas

plasma, injection, ECR, detector

159

G.S. Mauro, L. Celona, G. Torrisi, A. Pidatella, E. Naselli, F. Russo, B. Mishra, G. Finocchiaro, D. Santonocito, D. Mascali
INFN-LNS, Catania, Italy
A. Galatà
INFN-LNL, Legnaro (PD), Italy

The main aim of Plasmas for Astrophysics Nuclear Decays Observation and Radiation for Archaeometry (PANDORA) project is to build a flexible magnetic plasma trap where plasma reaches a density nₑ ∼ 10¹¹ – 10¹³ cm⁻³, and a temperature, in units of kT, kTₑ ∼ 0.1 – 30 keV in order to measure, for the first time, nuclear β-decay rates in stellar-like conditions. Here we present the numerical design of the PANDORA magnetic system, carried out by using the commercial simulators OPERA and CST Studio Suite. In particular, we discuss the design choices taken to: 1) obtain the required magnetic field levels at relevant axial and radial positions; 2) avoid the magnetic branches along the plasma chamber wall; 3) find the optimal position for the set of plasma diagnostics that will be employed. The magnetic trap has been conceived to be as large as possible, both in radial and axial directions, in order to exploit the plasma confinement mechanism on a bigger plasmoid volume. The plasma chamber will have a length of 700 mm and a diameter of 280 mm. The magnetic trap tender procedure has been completed in June 2024 and the structure realization is expected to start in late 2024.

Slides THA2 [6.420 MB]

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reference for this paper ※ doi:10.18429/JACoW-ECRIS2024-THA2

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Received ※ 25 January 2025 — Revised ※ 28 January 2025 — Accepted ※ 30 January 2025 — Issued ※ 15 June 2025

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