ECRIS2020 - Classification: 06: Codes and Simulations

Paper	Title	Page
TUYZO01	Advancements in Self-Consistent Modeling of Time- and Space-Dependent Phenomena in ECRIS Plasma	78
	A. Pidatella, D. Mascali, B. Mishra, E. Naselli, G. Torrisi INFN/LNS, Catania, Italy A. Galatà INFN/LNL, Legnaro (PD), Italy E. Naselli Catania University, Catania, Italy
	Resonant interaction with microwave radiation in ECRIS plasma leads to a strongly anisotropic electron energy distribution function (EEDF), given as a combination of two to three electron populations, with anisotropy that might trigger kinetic instabilities. At the INFN, further efforts have been paid to improve and update self-consistent 3D numerical codes for plasma electrons kinetics. Progresses have opened several perspectives. It is now possible to derive a space-resolved EEDF, providing local information on electron properties. Also, the code has been updated to provide reaction rates of electromagnetic emissions, including X-ray fluorescence. Estimates of the local ion charge state distribution is potentially possible, and first evaluations are ongoing. Dealing with fast-transient mechanisms, such as electromagnetic emission via the electron-cyclotron MASER instability, the code is now updated for locally evaluating the EEDF anisotropy. We will present the collected results, which we believe to have a relevant impact both on the ECRIS plasma physics and on the INFN’s PANDORA project that plans to use ECR plasmas for fundamental studies in Nuclear and AstroNuclear Physics.
	Slides TUYZO01 [25.158 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-TUYZO01
About •	Received ※ 28 September 2020 — Revised ※ 03 October 2020 — Accepted ※ 21 November 2020 — Issue date ※ 01 December 2020
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUYZO02	A Guiding Centre Approximation Approach for Simulation Electron Trajectories in ECR and Microwave Ion Sources	84
	J.A. Méndez, T. Thuillier LPSC, Grenoble Cedex, France T. Minea CNRS LPGP Univ Paris Sud, Orsay, France
	Funding: Work supported by the CNRS under the 80\|PRIME grant This work presents a study on the feasibility of the implementation of the guiding centre (GC) approach in electron cyclotron resonance (ECR) ion sources, with the goal of speeding up the electron’s orbit integration in certain regimes. It is shown that the GC approximation reproduces accurately the trajectory drifts and periodic behaviour of electrons in the minimum-B field. A typical electron orbit far enough from the source’s axis is well reproduced for 1 µs of propagation time, with the GC time-step constrained below 100 ps, giving one order of magnitude gain in computation time with respect to Boris. For an electron orbit close to the axis a disphasement of the electron’s trajectory is observed, but the spatial envelope is conserved. A comparative study analyses electron trajectories in a flatter B-field, that in a microwave discharge ion source, where this method’s drawbacks may be avoided given a smaller magnetic field gradient and a shorter electron lifetime in the plasma chamber. In this regime electron trajectories were very well reproduced by the GC approximation. The time-step was constrained below 10 ns, providing up to 30 times faster integration compared to Boris.
	Slides TUYZO02 [5.829 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-TUYZO02
About •	Received ※ 28 September 2020 — Revised ※ 21 December 2020 — Accepted ※ 18 May 2021 — Issue date ※ 02 February 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUYZO03	Electromagnetic Simulation of "plasma-shaped" Plasma Chamber for Innovative ECRIS	90
	G.S. Mauro, O. Leonardi, D. Mascali, A. Pidatella, F. Russo, G. Sorbello, G. Torrisi INFN/LNS, Catania, Italy A. Galatà, C.S. Gallo INFN/LNL, Legnaro (PD), Italy C.S. Gallo UNIFE, Ferrara, Italy G. Sorbello University of Catania, Catania, Italy
	The plasma chamber and injection system design play a fundamental role in ECRISs with the aim to obtain an optimized electromagnetic field configuration able to generate and sustain a plasma with a high energy content. In this work we present the numerical study and the design of an unconventionally-shaped cavity resonator* that possesses some key advantages with respect to the standard cylindrical cavities, usually adopted in ion sources setups. The cavity geometry, whose design has been completed on January 2020, has been inspired by the typical star-shaped ECR plasma, determined by the magnetic field structure. The chamber has been designed by using the commercial softwares CST and COMSOL, with the aim to maximize the on-axis electric field. Moreover, a radically innovative microwaves injection system, consisting in side-coupled slotted waveguides, has been implemented, allowing a better power coupling and a more symmetric power distribution inside the cavity with respect to the standard rectangular waveguides. This new ’plasma-shaped oriented’ design could relevantly improve the performances of the ECRISs while making more compact the overall setup. *This work has been carried out within the Grant 73/IRIS project, supported by INFN (Italian patent pending n. 102020000001756).
	Slides TUYZO03 [5.119 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-TUYZO03
About •	Received ※ 28 September 2020 — Revised ※ 05 October 2020 — Accepted ※ 18 May 2021 — Issue date ※ 10 December 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEXZO03	Conceptual Design of an Electrostatic Trap for High Intensity Pulsed Beam	132
	W. Huang, Y.G. Liu, L.T. Sun, H.W. Zhao IMP/CAS, Lanzhou, People’s Republic of China L.T. Sun UCAS, Beijing, People’s Republic of China D.Z. Xie LBNL, Berkeley, California, USA
	Funding: China Scholarship Council (CSC) (No. 201904910324) Highly charged ion sources play an important role in the advancement of heavy ion accelerators worldwide. The beam requirements of highly charged heavy ions from new accelerators have driven the performance of ion sources to their limits and beyond. In parallel to developing new technologies to enhance the performance of ECR ion source, this paper presents a conceptual design of an ion trap aiming to convert a cw ion beam into a short beam pulse with high compression ratios. With an electron gun, a solenoid and a set of drift tubes, the injected ions will be trapped radially and axially. By manipulating the potential of drift tubes, ions can be accumulated with multiple injections and extracted at a fast or slow scheme. This paper presents the simulation and design results of this ion trap prototype.
	Slides WEXZO03 [0.910 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEXZO03
About •	Received ※ 21 September 2020 — Revised ※ 01 January 2021 — Accepted ※ 14 April 2021 — Issue date ※ 14 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEXZO04	Numerical Simulations of Plasma Dynamics in ECRIS Afterglow
	L. Lei, X.L. Jin University of Electronic Science and Technology of China, Chengdu, People’s Republic of China J.B. Li IMP/CAS, Lanzhou, People’s Republic of China
	Plasma dynamics in the afterglow of ECRIS has been studied through the Particle-in-cell (PIC) simulations. A full 3D implicit electrostatic PIC code was developed to meet the needs of ECRIS simulations and to study the characteristics of the ECR plasma during the afterglow. The initial plasma parameters at the simulation start-up were assumed by referring to the experimental diagnostics of the ECRISs from IMP, Lanzhou. The dynamics of electrons and ions in the presence of the external magnetic field and at the absence of the microwave energy were simulated to study the mechanism of afterglow. Through the abundant diagnostics of the 3D PIC simulation, some ECR plasma features during afterglow including the plasma potential and electron energy distributions could be obtained and analyzed. The goal was to determine the important evolutions that contribute to the afterglow and thus to have a clearer understanding of ECRIS afterglow mode.
	Slides WEXZO04 [0.952 MB]
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Advancements in Self-Consistent Modeling of Time- and Space-Dependent Phenomena in ECRIS Plasma

78

A. Pidatella, D. Mascali, B. Mishra, E. Naselli, G. Torrisi
INFN/LNS, Catania, Italy
A. Galatà
INFN/LNL, Legnaro (PD), Italy
E. Naselli
Catania University, Catania, Italy

Resonant interaction with microwave radiation in ECRIS plasma leads to a strongly anisotropic electron energy distribution function (EEDF), given as a combination of two to three electron populations, with anisotropy that might trigger kinetic instabilities. At the INFN, further efforts have been paid to improve and update self-consistent 3D numerical codes for plasma electrons kinetics. Progresses have opened several perspectives. It is now possible to derive a space-resolved EEDF, providing local information on electron properties. Also, the code has been updated to provide reaction rates of electromagnetic emissions, including X-ray fluorescence. Estimates of the local ion charge state distribution is potentially possible, and first evaluations are ongoing. Dealing with fast-transient mechanisms, such as electromagnetic emission via the electron-cyclotron MASER instability, the code is now updated for locally evaluating the EEDF anisotropy. We will present the collected results, which we believe to have a relevant impact both on the ECRIS plasma physics and on the INFN’s PANDORA project that plans to use ECR plasmas for fundamental studies in Nuclear and AstroNuclear Physics.

Slides TUYZO01 [25.158 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-TUYZO01

About •

Received ※ 28 September 2020 — Revised ※ 03 October 2020 — Accepted ※ 21 November 2020 — Issue date ※ 01 December 2020

Cite •

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

TUYZO02

A Guiding Centre Approximation Approach for Simulation Electron Trajectories in ECR and Microwave Ion Sources

84

J.A. Méndez, T. Thuillier
LPSC, Grenoble Cedex, France
T. Minea
CNRS LPGP Univ Paris Sud, Orsay, France

Funding: Work supported by the CNRS under the 80|PRIME grant
This work presents a study on the feasibility of the implementation of the guiding centre (GC) approach in electron cyclotron resonance (ECR) ion sources, with the goal of speeding up the electron’s orbit integration in certain regimes. It is shown that the GC approximation reproduces accurately the trajectory drifts and periodic behaviour of electrons in the minimum-B field. A typical electron orbit far enough from the source’s axis is well reproduced for 1 µs of propagation time, with the GC time-step constrained below 100 ps, giving one order of magnitude gain in computation time with respect to Boris. For an electron orbit close to the axis a disphasement of the electron’s trajectory is observed, but the spatial envelope is conserved. A comparative study analyses electron trajectories in a flatter B-field, that in a microwave discharge ion source, where this method’s drawbacks may be avoided given a smaller magnetic field gradient and a shorter electron lifetime in the plasma chamber. In this regime electron trajectories were very well reproduced by the GC approximation. The time-step was constrained below 10 ns, providing up to 30 times faster integration compared to Boris.

Slides TUYZO02 [5.829 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-TUYZO02

About •

Received ※ 28 September 2020 — Revised ※ 21 December 2020 — Accepted ※ 18 May 2021 — Issue date ※ 02 February 2022

Cite •

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

TUYZO03

Electromagnetic Simulation of "plasma-shaped" Plasma Chamber for Innovative ECRIS

90

G.S. Mauro, O. Leonardi, D. Mascali, A. Pidatella, F. Russo, G. Sorbello, G. Torrisi
INFN/LNS, Catania, Italy
A. Galatà, C.S. Gallo
INFN/LNL, Legnaro (PD), Italy
C.S. Gallo
UNIFE, Ferrara, Italy
G. Sorbello
University of Catania, Catania, Italy

The plasma chamber and injection system design play a fundamental role in ECRISs with the aim to obtain an optimized electromagnetic field configuration able to generate and sustain a plasma with a high energy content. In this work we present the numerical study and the design of an unconventionally-shaped cavity resonator* that possesses some key advantages with respect to the standard cylindrical cavities, usually adopted in ion sources setups. The cavity geometry, whose design has been completed on January 2020, has been inspired by the typical star-shaped ECR plasma, determined by the magnetic field structure. The chamber has been designed by using the commercial softwares CST and COMSOL, with the aim to maximize the on-axis electric field. Moreover, a radically innovative microwaves injection system, consisting in side-coupled slotted waveguides, has been implemented, allowing a better power coupling and a more symmetric power distribution inside the cavity with respect to the standard rectangular waveguides. This new ’plasma-shaped oriented’ design could relevantly improve the performances of the ECRISs while making more compact the overall setup.
*This work has been carried out within the Grant 73/IRIS project, supported by INFN (Italian patent pending n. 102020000001756).

Slides TUYZO03 [5.119 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-TUYZO03

About •

Received ※ 28 September 2020 — Revised ※ 05 October 2020 — Accepted ※ 18 May 2021 — Issue date ※ 10 December 2021

Cite •

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

WEXZO03

Conceptual Design of an Electrostatic Trap for High Intensity Pulsed Beam

132

W. Huang, Y.G. Liu, L.T. Sun, H.W. Zhao
IMP/CAS, Lanzhou, People’s Republic of China
L.T. Sun
UCAS, Beijing, People’s Republic of China
D.Z. Xie
LBNL, Berkeley, California, USA

Funding: China Scholarship Council (CSC) (No. 201904910324)
Highly charged ion sources play an important role in the advancement of heavy ion accelerators worldwide. The beam requirements of highly charged heavy ions from new accelerators have driven the performance of ion sources to their limits and beyond. In parallel to developing new technologies to enhance the performance of ECR ion source, this paper presents a conceptual design of an ion trap aiming to convert a cw ion beam into a short beam pulse with high compression ratios. With an electron gun, a solenoid and a set of drift tubes, the injected ions will be trapped radially and axially. By manipulating the potential of drift tubes, ions can be accumulated with multiple injections and extracted at a fast or slow scheme. This paper presents the simulation and design results of this ion trap prototype.

Slides WEXZO03 [0.910 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEXZO03

About •

Received ※ 21 September 2020 — Revised ※ 01 January 2021 — Accepted ※ 14 April 2021 — Issue date ※ 14 July 2022

Cite •

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

WEXZO04

Numerical Simulations of Plasma Dynamics in ECRIS Afterglow

L. Lei, X.L. Jin
University of Electronic Science and Technology of China, Chengdu, People’s Republic of China
J.B. Li
IMP/CAS, Lanzhou, People’s Republic of China

Plasma dynamics in the afterglow of ECRIS has been studied through the Particle-in-cell (PIC) simulations. A full 3D implicit electrostatic PIC code was developed to meet the needs of ECRIS simulations and to study the characteristics of the ECR plasma during the afterglow. The initial plasma parameters at the simulation start-up were assumed by referring to the experimental diagnostics of the ECRISs from IMP, Lanzhou. The dynamics of electrons and ions in the presence of the external magnetic field and at the absence of the microwave energy were simulated to study the mechanism of afterglow. Through the abundant diagnostics of the 3D PIC simulation, some ECR plasma features during afterglow including the plasma potential and electron energy distributions could be obtained and analyzed. The goal was to determine the important evolutions that contribute to the afterglow and thus to have a clearer understanding of ECRIS afterglow mode.

Slides WEXZO04 [0.952 MB]

Cite •

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