ECRIS2020 - List of Keywords (electron)

Paper	Title	Other Keywords	Page
MOWZO02	LECR5 Development and Status Report	ECR, ion-source, resonance, MMI	6
	C. Qian, J.R. An, J.J. Chang, X. Fang, Y.C. Feng, J.W. Guo, Z.H. Jia, L.B. Li, W. Lu, J.D. Ma, Y.M. Ma, L.T. Sun, H. Wang, X.Z. Zhang, H.W. Zhao IMP/CAS, Lanzhou, People’s Republic of China C. Qian University of Chinese Academy of Sciences, Beijing, People’s Republic of China
	LECR5 (Lanzhou Electron Cyclotron Resonance ion source No. 5) is an 18 GHz room temperature ECR ion source featuring Ø80 mm ID (Internal Diameter) plasma chamber and high magnetic fields. It has been successfully constructed at IMP recently and has been fully commissioned to meet the requirements of SESRI (Space Environment Simulation and Research Infrastructure) project. According to the test results, LECR5 can meet the requirements of SESRI with sufficient beam intensities within the required the transverse emittances. As LECR5 is designed to be optimal for the operation at 18 GHz, we have managed to explore the source performance at 18 GHz with a maximum microwave power around 2 kW. Recent source test indicates, LECR5 can produce not only high intensity ion beams such as 2.12 emA O⁶⁺, 121 e’A of Ar¹⁴⁺, 73 e’A of Kr²³⁺, 145 e’A of Xe²⁷⁺, but also very high charge state ion beams such as 22 e’A of Bi⁴¹⁺. This paper will present the recent progress with LECR5, especially the intense ion beam production and the beam quality investigation.
	Slides MOWZO02 [5.886 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-MOWZO02
About •	Received ※ 27 September 2020 — Revised ※ 30 December 2020 — Accepted ※ 18 May 2021 — Issue date ※ 14 November 2021
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MOYZO01	Imaging in X-ray Ranges to Locally Investigate the Effect of the Two-Close-Frequency Heating in ECRIS Plasmas	plasma, ECR, experiment, operation	27
	R. Rácz, S. Biri, Z. Perduk Atomki, Debrecen, Hungary G. Castro, L. Celona, S. Gammino, D. Mascali, M. Mazzaglia, E. Naselli, G. Torrisi INFN/LNS, Catania, Italy A. Galatà INFN/LNL, Legnaro (PD), Italy E. Naselli Catania University, Catania, Italy J. Pálinkás University Debrecen, Debrecen, Hungary
	Plasma instabilities limit the ECR Ion Sources performances in terms of flux of the extracted highly charged ions by causing beam ripple and unstable operation conditions. In a 14 GHz ECRIS (Atomki, Debrecen), the effect on the plasma instabilities in an Argon plasma at Two Close Frequencies heating scheme (the frequency gap is smaller than 1 GHz) has been explored. A special multi-diagnostic setup [1, 2] has been designed and implemented consisting of detectors for the simultaneous collection of plasma radio-self-emission and of high spatial resolution X-ray images in the 500 eV - 20 keV energy domain (using an X-ray pin-hole camera setup). We present the comparison of plasma structural changes as observed from X-ray images in single and double-frequency operations. The latter has been particularly correlated to the confinement and velocity anisotropy, also by considering results coming from numerical simulations. [1] S. Biri et al. Journal of Instrumentation 13(11):C11016 DOI: 10.1088/1748-0221/13/11/C11016 [2] E. Naselli et. al. Journal of Instrumentation 14(10):C10008 DOI: 10.1088/1748-0221/14/10/C10008
	Slides MOYZO01 [7.325 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-MOYZO01
About •	Received ※ 25 September 2020 — Revised ※ 11 November 2020 — Accepted ※ 17 December 2020 — Issue date ※ 24 January 2021
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MOYZO02	High Resolution X-ray Imaging as a Powerful Diagnostics Tool to Investigate ECRIS Plasma Structure and Confinement Dynamics	plasma, photon, ECR, ion-source	32
	E. Naselli, G. Castro, L. Celona, S. Gammino, D. Mascali, M. Mazzaglia, G. Torrisi INFN/LNS, Catania, Italy S. Biri, Z. Perduk, R. Rácz Atomki, Debrecen, Hungary A. Galatà INFN/LNL, Legnaro (PD), Italy E. Naselli Catania University, Catania, Italy J. Pálinkás DU, Debrecen, Hungary
	High resolution spatially-resolved X-ray spectroscopy, by means of a X-ray pin-hole camera setup* ** operating in the 0.5-20 keV energy domain, is a very powerful method for ECRIS plasma structure evaluation. We present the setup installed at a 14 GHz ECRIS (ATOMKI, Debrecen), including a multi-layered collimator enabling measurements up to several hundreds of watts of RF pumping power and the achieved spatial and energy resolution (0.5 mm and 300 eV). Results coming by a new algorithm for analyzing Integrated (multi-events detection) and Photon-Counted images (single-event detection) to perform energy-resolved investigation will be described. The analysis permits to investigate High-Dynamic-Range (HDR) and spectrally resolved images, to study the effect of the axial and radial confinement (even separately), the plasma radius, the fluxes of deconfined electrons distinguishing fluorescence lines of the materials of the plasma chamber (Ti, Ta) from plasma (Ar) fluorescence lines. This method allows a detailed characterization of warm electrons, important for ionization, and to quantitatively estimate local plasma density and spectral temperature pixel-by-pixel. S. Biri et al., JINST 13(11):C11016-C11016, DOI:10.1088/1748-0221/13/11/C11016 *E. Naselli et al., JINST 14(10):C10008-C10008, DOI:10.1088/1748-0221/14/10/C10008
	Slides MOYZO02 [26.629 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-MOYZO02
About •	Received ※ 27 September 2020 — Revised ※ 02 October 2020 — Accepted ※ 18 November 2020 — Issue date ※ 17 December 2020
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MOYZO03	The Relationship Between the Diffusion of Hot Electrons, Plasma Stability, and ECR Ion Source Performance	plasma, ECR, ion-source, cyclotron	38
	B.C. Isherwood MSU, East Lansing, Michigan, USA G. Machicoane NSCL, East Lansing, Michigan, USA G. Machicoane FRIB, East Lansing, Michigan, USA
	Funding: This research was made possible by the National Science Foundation under NSF Grant 1632761 and the U.S. Department of Energy Award Number DE-SC0018362. Plasma instabilities complicate the operation of electron cyclotron resonance ion sources. In particular, quasi-periodic losses of electrons from confinement due to kinetic cyclotron instabilities hinder ion source performance. Empirical scaling laws help guide the development of sources away from the most unstable operating points but are poorly understood. Further advancement of ECR ion source technologies requires a deeper understanding of instabilities, scaling laws, and internal processes of the ion source plasma itself. We present here results of an experimental study into these instabilities and scaling laws, and measurements of hot electron diffusion (E > 10 keV) from the 18 GHz SUSI ECRIS at the NSCL. Measurements of the average argon current and the standard deviation of their variations across multiple unstable operating points are shown. These measurements are compared to measurements of electrons that diffuse axially from the plasma chamber. In doing so it will be shown how controlling the diffusion of electrons control the stability of the plasma and optimize the ion source’s performance.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-MOYZO03
About •	Received ※ 30 September 2020 — Revised ※ 20 October 2020 — Accepted ※ 19 January 2021 — Issue date ※ 11 April 2022
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MOZZO06	Microcontrollers as Gate and Delay Generators for Time Resolved Measurements	plasma, ECR, ion-source, cyclotron	57
	B.C. Isherwood MSU, East Lansing, Michigan, USA G. Machicoane FRIB, East Lansing, Michigan, USA
	Funding: This research was made possible by the National Science Foundation under NSF Grant 1632761 and the U.S. Department of Energy Award Number DE-SC0018362. The diffusion of electrons from ECRIS plasmas results in the emission of bremsstrahlung distributions from the plasma chamber. ECRIS bremsstrahlung measurements that are both time- and energy-resolved are often challenging to perform due to the 10’s; 100’s ms timescale that the plasma evolves over. However, the advancement of low-cost microcontrollers over the last decade makes timing and gating photon spectrometers easier. We present a proof of principle measurement which uses an Arduino microcontroller as a gate-and-delay generator for a High Purity Germanium (HPGe) detector. An example plot of the time-resolved bremsstrahlung spectrum, triggered by beam current variation induced by kinetic instabilities, is shown.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-MOZZO06
About •	Received ※ 30 September 2020 — Revised ※ 21 October 2020 — Accepted ※ 19 January 2021 — Issue date ※ 23 December 2021
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TUWZO01	Measurements of Plasma Parameters Near Resonance Zones and Peripheral Regions in ECRIS	ECR, dipole, plasma, ECRIS	60
	W. Kubo, S. Harisaki, Y. Kato, I. Owada, K. Sato, K. Tsuda Osaka University, Graduate School of Engineering, Osaka, Japan
	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).
	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
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TUXZO01	A Proposed Explanation of High-Minimum-B Instabilities	resonance, ECR, ion-source, plasma	68
	D.S. Todd, J.Y. Benitez LBNL, Berkeley, California, USA
	It is well-known that electron cyclotron resonance ion sources exhibit instabilities when these sources’ minimum magnetic fields are approximately 80% of the resonant field or greater, but the reasons for this instability have yet to be satisfactorily explained. We show that raising the minimum field makes much faster heating modes accessible at lower energies that invite the onset of kinetic instabilities.
	Slides TUXZO01 [3.566 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-TUXZO01
About •	Received ※ 28 September 2020 — Revised ※ 06 October 2020 — Accepted ※ 03 December 2020 — Issue date ※ 13 December 2020
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TUYZO01	Advancements in Self-Consistent Modeling of Time- and Space-Dependent Phenomena in ECRIS Plasma	plasma, ECR, ECRIS, cyclotron	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
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TUYZO02	A Guiding Centre Approximation Approach for Simulation Electron Trajectories in ECR and Microwave Ion Sources	ion-source, plasma, ECR, GUI	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
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TUZZO02	Electron Cyclotron Resonance Ion Source Related Research and Development Work at the Department of Physics, University of Jyväskylä (JYFL)	ECR, ECRIS, plasma, ion-source	98
	H.A. Koivisto, B.S. Bhaskar, A. Ikonen, T. Kalvas, S.T. Kosonen, R.J. Kronholm, M.S.P. Marttinen, O.P.I. Timonen, V. Toivanen JYFL, Jyväskylä, Finland J. Angot, B.S. Bhaskar, T. Thuillier LPSC, Grenoble Cedex, France I. Izotov, V. Skalyga IAP/RAS, Nizhny Novgorod, Russia L. Maunoury GANIL, Caen, France O.A. Tarvainen STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
	Funding: The work has received funding from the Academy of Finland under the Academy of Finland Project funding (No. 315855) and from University Grenoble Alps under EMERGENCE-project. Recent research work of the JYFL ion source team covers multi-diagnostic studies of plasma instabilities, high-resolution plasma optical emission spectroscopy, ion current transient measurements to define the total life-time of a particle in the highly charged plasma. The JYFL team also elaborates the magnetic and technical design of the unconventional ion source named CUBE. The R&D work includes, in addition, the commissioning and operation of the high-performance 18 GHz ECRIS, HIISI. The instability measurements have revealed new information about the parameters affecting the onset of the plasma instabilities and shown that different instability modes exist. The ion-beam transient studies have given information about the cumulative life-time of highly-charged ions convergent with the ion temperatures deduced from the Doppler broadening of emission lines. The CUBE prototype has a minimum-B quadrupole magnetic field topology, similar to ARC-ECRIS, and its all-permanent magnet structure has been optimized for 10 GHz frequency. The CUBE design will be presented along with its commissioning status. The status and operational experience with HIISI will be reported as well.
	Slides TUZZO02 [9.553 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-TUZZO02
About •	Received ※ 28 September 2020 — Revised ※ 09 November 2020 — Accepted ※ 03 December 2020 — Issue date ※ 05 May 2021
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WEWZO05	Beam Profile Measurements of Decelerated Multicharged Xe Ions from ECRIS for Estimating Low Energy Damage on Satellites Components	radiation, experiment, ECR, ECRIS	125
	K. Sato, S. Harisaki, Y. Kato, W. Kubo, K. Okumura, I. Owada, K. Tsuda Osaka University, Graduate School of Engineering, Osaka, Japan
	Electron cyclotron resonance ion source (ECRIS) has been constructed for producing synthesized ion beams in Osaka Univ.,* Xe is used as fuel for ion propulsion engines on artificial satellites. There are problems of accumulated damages at irradiation and sputtering by low energy Xe ion from the engine. It is required to construct experimentally sputtering yield databases of ion beams in the low energy region from several hundred eV to 1keV, since there are not enough data of satellite component materials. Therefore, we are trying to investigate experimentally sputtering yield on materials by irradiating the low energy single species Xeq+ ion beams. However, there is a problem that if the low extraction voltage, the amount of beam currents is not enough to obtain ion beam flux for precise evaluation of sputtering yield data. Thus, we conduct to decelerate Xeq+ ion beams required low energy region after extracting at high voltage, e.g., 10kV. We measured the decelerated beam profile with x and y direction wire probes. As a result, we were able to estimate the dose of ion fluxes. We are going to conduct irradiation experiments on various materials. Y. Kato, et al., RSI, 2014, 85, 02A950-1-3. *Y. Kato, et al., RSI, 2016, 87, 02A710-1-4.
	Slides WEWZO05 [8.964 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEWZO05
About •	Received ※ 27 September 2020 — Revised ※ 25 September 2020 — Accepted ※ 29 September 2020 — Issue date ※ 14 July 2022
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WEXZO03	Conceptual Design of an Electrostatic Trap for High Intensity Pulsed Beam	ECR, ion-source, simulation, extraction	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
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WEYZO02	Design of a 2.45 GHz Surface Wave Plasma Source for Plasma Flood Gun	plasma, ECR, ion-source, coupling	143
	S.X. Peng, J.E. Chen, B.J. Cui, Z.Y. Guo, Y.X. Jiang, K. Li, T.H. Ma, J.M. Wen, W.B. Wu, Y. Xu, A.L. Zhang, J.F. Zhang, T. Zhang PKU, Beijing, People’s Republic of China
	Plasma ’ood guns (PFGs) are widely used to neutralize wafer charge during the doping process in modern ion implanters. Compared with traditional dc arc discharge with filament and RF discharge, the microwave driven source that has long lifetime and has no metallic contamination is regarded as a potential choice of PFG [1]. Attempt to develop a large scale PFG based on 2.45 GHz microwave driven sources was launched at Peking University (PKU). A prototype one is a miniaturized 2.45 GHz permanent magnet electron cyclotron resonance (ECR) source to produce point-like electron beam. In previous experiments, more than 8 mA electron beam has been extracted with a ’6 mm extraction hole at an input microwave power of 22 W with argon gas [2]. Recently, studies are focusing on the possibility of producing of ribbon electron beams as PFG with 2.45GHz microwave driven surface wave plasma (SWP) source. A cylindrical chamber surface wave plasma generator with a using cylindrical dielectric waveguide and a 70 mm×3 mm extraction slit was fabricated. The primary test results were obtained. More details of this PFGs will be discussed in this work. References [1] B. Vanderberg, et al. AIP Conference Proceedings, 1496(1), 356 (2012). [2] Yaoxiang Jiang, Shixiang Peng, et al, Review of Scientific Instruments, 91, 033319 (2020).
	Slides WEYZO02 [5.475 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEYZO02
About •	Received ※ 28 September 2020 — Revised ※ 29 December 2020 — Accepted ※ 25 April 2022 — Issue date ※ 14 July 2022
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WEZZO10	Electron Cyclotron Emission Imaging of Electron Cyclotron Resonance Ion Source Plasmas	plasma, ECR, ECRIS, cyclotron	164
	L.E. Henderson, H.L. Clark, C.A. Gagliardi Texas A&M University, Cyclotron Institute, College Station, Texas, USA D.P. May Texas A&M University Cyclotron Institute, College Station, Texas, USA
	A new imaging system for Electron Cyclotron Resonance Ion Sources (ECRIS) has been designed and is being built. This K- and Ka-band camera will extract localized measurements of absolute energy and relative number density for ECRIS plasma electrons by imaging their Electron Cyclotron Emission (ECE) spectra, as the frequency, shape, and strength of the ECE harmonics correlate directly with the local magnetic field, electron energy, and plasma density. The design of the overall quasi-optical system will be presented, including novel ceramic optics for the radial viewports of the Cyclotron Institute’s ECRIS and metamaterial mirrors with electronically controllable reflectivity. Spatial resolution sufficient to distinguish important plasma regions and temporal resolution sufficient to study dynamic plasma processes is expected.
	Slides WEZZO10 [10.583 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEZZO10
About •	Received ※ 28 September 2020 — Revised ※ 07 October 2020 — Accepted ※ 15 October 2020 — Issue date ※ 16 November 2020
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NACB02	Status of the High-Current EBIS Charge Breeder for the Facility for Rare Isotope Beams	cathode, simulation, gun, space-charge	172
	H.J. Son, A.I. Henriques, C. Knowles, A.C.C. Villari FRIB, East Lansing, Michigan, USA E.N. Beebe BNL, Upton, New York, USA D.B. Crisp, A. Lapierre, S. Nash NSCL, East Lansing, Michigan, USA
	Funding: work supported by the National Science Foundation under Grant No. PHY-1565546 The ReA post-accelerator of the National Supercon-ducting Cyclotron Laboratory (NSCL) at Michigan State University includes an Electron-Beam Ion Trap (EBIT) operating as a charge breeder. The Facility for Rare Iso-tope Beams (FRIB) is being implemented. After comple-tion, rare-isotopes beam rates are expected to exceed in some case 10<sup>10</sup> particles per second (pps). The charge capacity of the ReA EBIT is insufficient to handle those rates. Therefore, parts of the TEST EBIS from the Brookhaven National Laboratory (BNL) were transferred to the NSCL to build a High-Current Electron-Beam Ion Source (HCEBIS). The HCEBIS features an electron gun that can provide a current up to 4 A for an estimated trap charge capacity of 10<sup>11</sup> elementary charges. This paper presents the HCEBIS specifications, electron-beam cur-rent measurements to test its cathode, and simulation results for its implementation in the ReA post-accelerator. It also presents charge-capacity measurements conducted with the ReA EBIT that demonstrate that the HCEBIS will be able to handle beam rates of more than 10<sup>10</sup> pps.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-NACB02
About •	Received ※ 30 September 2020 — Revised ※ 01 October 2020 — Accepted ※ 30 November 2020 — Issue date ※ 13 March 2021
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NACB03	Determining the Fraction of Extracted 3He in the 3He²⁺ Charge State	simulation, acceleration, collider, rfq	177
	M.K. Gronert, E.N. Beebe BNL, Upton, New York, USA M.K. Gronert Drew University, Madison, New Jersey, USA
	Funding: Work supported by the US Department of Energy under contract number DE-SC0012704 and by the National Aeronautics and Space Administration The parameter space of the TOF was explored using analytic methods as well as computer simulation to improve the design and functionality of a similar device that was constructed as a prototype for the Electron Beam Ion Source (EBIS) in 2019. A simulation of the beam line optics was produced in Opera-2D CAD software to show that other optical elements would not materially affect the operation of the TOF. This will allow for true measurements of the charge state ratios of helium for EBIS and extended EBIS operation in support of the Electron Ion Collider. EBIS operators will use the device to maximize the fraction of 3He ions in the 3He²⁺ state. Different geometries were explored as well to maximize the effectiveness of the device and to meet the performance criterion and physical constraints of the EBIS beam line.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-NACB03
About •	Received ※ 14 October 2020 — Revised ※ 29 October 2020 — Accepted ※ 19 May 2021 — Issue date ※ 19 July 2021
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NACB04	Ion Simulations, Recent Upgrades and Tests with Titan’s Cooler Penning Trap	plasma, simulation, extraction, injection	181
	R. Silwal, J. Dilling, B.A. Kootte, A.A. Kwiatkowski, S.F. Paul TRIUMF, Vancouver, Canada J. Dilling UBC & TRIUMF, Vancouver, British Columbia, Canada G. Gwinner, B.A. Kootte University of Manitoba, Manitoba, Canada R. Simpson UW/Physics, Waterloo, Ontario, Canada
	TRIUMF’s Ion Trap for Atomic and Nuclear science (TITAN) facility has the only on-line mass measurement Penning trap (MPET) at a radioactive beam facility that uses an electron beam ion trap (EBIT) to enhance mass precision and resolution. EBITs can charge breed exotic isotopes, making them highly charged, thereby improving the precision of atomic mass measurement as the precision scales linearly with the charge state. However, ion bunches charge bred in the EBIT can have larger energy spread, which poses challenges for mass measurements. A cooler Penning trap (CPET) is currently being developed off-line at TITAN to sympathetically cool the highly charged ions (HCI) with a co-trapped electron plasma, prior to their transport to the MPET. To evaluate the integration of the CPET into the TITAN beamline and to optimize the beam transport, ion trajectory simulations were performed. Hardware upgrades motivated by these simulations and previous test measurements were applied to the off-line CPET setup. Ions and electrons were co-trapped for the first time with the CPET. Progress and challenges on the path towards HCI cooling and integration with the on-line beam facility are presented
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-NACB04
About •	Received ※ 17 October 2020 — Revised ※ 23 October 2020 — Accepted ※ 01 December 2020 — Issue date ※ 07 February 2021
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Paper

Title

Other Keywords

Page

MOWZO02

LECR5 Development and Status Report

ECR, ion-source, resonance, MMI

6

C. Qian, J.R. An, J.J. Chang, X. Fang, Y.C. Feng, J.W. Guo, Z.H. Jia, L.B. Li, W. Lu, J.D. Ma, Y.M. Ma, L.T. Sun, H. Wang, X.Z. Zhang, H.W. Zhao
IMP/CAS, Lanzhou, People’s Republic of China
C. Qian
University of Chinese Academy of Sciences, Beijing, People’s Republic of China

LECR5 (Lanzhou Electron Cyclotron Resonance ion source No. 5) is an 18 GHz room temperature ECR ion source featuring Ø80 mm ID (Internal Diameter) plasma chamber and high magnetic fields. It has been successfully constructed at IMP recently and has been fully commissioned to meet the requirements of SESRI (Space Environment Simulation and Research Infrastructure) project. According to the test results, LECR5 can meet the requirements of SESRI with sufficient beam intensities within the required the transverse emittances. As LECR5 is designed to be optimal for the operation at 18 GHz, we have managed to explore the source performance at 18 GHz with a maximum microwave power around 2 kW. Recent source test indicates, LECR5 can produce not only high intensity ion beams such as 2.12 emA O⁶⁺, 121 e’A of Ar¹⁴⁺, 73 e’A of Kr²³⁺, 145 e’A of Xe²⁷⁺, but also very high charge state ion beams such as 22 e’A of Bi⁴¹⁺. This paper will present the recent progress with LECR5, especially the intense ion beam production and the beam quality investigation.

Slides MOWZO02 [5.886 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-MOWZO02

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Received ※ 27 September 2020 — Revised ※ 30 December 2020 — Accepted ※ 18 May 2021 — Issue date ※ 14 November 2021

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MOYZO01

Imaging in X-ray Ranges to Locally Investigate the Effect of the Two-Close-Frequency Heating in ECRIS Plasmas

plasma, ECR, experiment, operation

27

R. Rácz, S. Biri, Z. Perduk
Atomki, Debrecen, Hungary
G. Castro, L. Celona, S. Gammino, D. Mascali, M. Mazzaglia, E. Naselli, G. Torrisi
INFN/LNS, Catania, Italy
A. Galatà
INFN/LNL, Legnaro (PD), Italy
E. Naselli
Catania University, Catania, Italy
J. Pálinkás
University Debrecen, Debrecen, Hungary

Plasma instabilities limit the ECR Ion Sources performances in terms of flux of the extracted highly charged ions by causing beam ripple and unstable operation conditions. In a 14 GHz ECRIS (Atomki, Debrecen), the effect on the plasma instabilities in an Argon plasma at Two Close Frequencies heating scheme (the frequency gap is smaller than 1 GHz) has been explored. A special multi-diagnostic setup [1, 2] has been designed and implemented consisting of detectors for the simultaneous collection of plasma radio-self-emission and of high spatial resolution X-ray images in the 500 eV - 20 keV energy domain (using an X-ray pin-hole camera setup). We present the comparison of plasma structural changes as observed from X-ray images in single and double-frequency operations. The latter has been particularly correlated to the confinement and velocity anisotropy, also by considering results coming from numerical simulations.
[1] S. Biri et al. Journal of Instrumentation 13(11):C11016 DOI: 10.1088/1748-0221/13/11/C11016
[2] E. Naselli et. al. Journal of Instrumentation 14(10):C10008 DOI: 10.1088/1748-0221/14/10/C10008

Slides MOYZO01 [7.325 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-MOYZO01

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Received ※ 25 September 2020 — Revised ※ 11 November 2020 — Accepted ※ 17 December 2020 — Issue date ※ 24 January 2021

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MOYZO02

High Resolution X-ray Imaging as a Powerful Diagnostics Tool to Investigate ECRIS Plasma Structure and Confinement Dynamics

plasma, photon, ECR, ion-source

32

E. Naselli, G. Castro, L. Celona, S. Gammino, D. Mascali, M. Mazzaglia, G. Torrisi
INFN/LNS, Catania, Italy
S. Biri, Z. Perduk, R. Rácz
Atomki, Debrecen, Hungary
A. Galatà
INFN/LNL, Legnaro (PD), Italy
E. Naselli
Catania University, Catania, Italy
J. Pálinkás
DU, Debrecen, Hungary

High resolution spatially-resolved X-ray spectroscopy, by means of a X-ray pin-hole camera setup* ** operating in the 0.5-20 keV energy domain, is a very powerful method for ECRIS plasma structure evaluation. We present the setup installed at a 14 GHz ECRIS (ATOMKI, Debrecen), including a multi-layered collimator enabling measurements up to several hundreds of watts of RF pumping power and the achieved spatial and energy resolution (0.5 mm and 300 eV). Results coming by a new algorithm for analyzing Integrated (multi-events detection) and Photon-Counted images (single-event detection) to perform energy-resolved investigation will be described. The analysis permits to investigate High-Dynamic-Range (HDR) and spectrally resolved images, to study the effect of the axial and radial confinement (even separately), the plasma radius, the fluxes of deconfined electrons distinguishing fluorescence lines of the materials of the plasma chamber (Ti, Ta) from plasma (Ar) fluorescence lines. This method allows a detailed characterization of warm electrons, important for ionization, and to quantitatively estimate local plasma density and spectral temperature pixel-by-pixel.
*S. Biri et al., JINST 13(11):C11016-C11016, DOI:10.1088/1748-0221/13/11/C11016
**E. Naselli et al., JINST 14(10):C10008-C10008, DOI:10.1088/1748-0221/14/10/C10008

Slides MOYZO02 [26.629 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-MOYZO02

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Received ※ 27 September 2020 — Revised ※ 02 October 2020 — Accepted ※ 18 November 2020 — Issue date ※ 17 December 2020

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MOYZO03

The Relationship Between the Diffusion of Hot Electrons, Plasma Stability, and ECR Ion Source Performance

plasma, ECR, ion-source, cyclotron

38

B.C. Isherwood
MSU, East Lansing, Michigan, USA
G. Machicoane
NSCL, East Lansing, Michigan, USA
G. Machicoane
FRIB, East Lansing, Michigan, USA

Funding: This research was made possible by the National Science Foundation under NSF Grant 1632761 and the U.S. Department of Energy Award Number DE-SC0018362.
Plasma instabilities complicate the operation of electron cyclotron resonance ion sources. In particular, quasi-periodic losses of electrons from confinement due to kinetic cyclotron instabilities hinder ion source performance. Empirical scaling laws help guide the development of sources away from the most unstable operating points but are poorly understood. Further advancement of ECR ion source technologies requires a deeper understanding of instabilities, scaling laws, and internal processes of the ion source plasma itself. We present here results of an experimental study into these instabilities and scaling laws, and measurements of hot electron diffusion (E > 10 keV) from the 18 GHz SUSI ECRIS at the NSCL. Measurements of the average argon current and the standard deviation of their variations across multiple unstable operating points are shown. These measurements are compared to measurements of electrons that diffuse axially from the plasma chamber. In doing so it will be shown how controlling the diffusion of electrons control the stability of the plasma and optimize the ion source’s performance.

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reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-MOYZO03

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Received ※ 30 September 2020 — Revised ※ 20 October 2020 — Accepted ※ 19 January 2021 — Issue date ※ 11 April 2022

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MOZZO06

Microcontrollers as Gate and Delay Generators for Time Resolved Measurements

plasma, ECR, ion-source, cyclotron

57

B.C. Isherwood
MSU, East Lansing, Michigan, USA
G. Machicoane
FRIB, East Lansing, Michigan, USA

Funding: This research was made possible by the National Science Foundation under NSF Grant 1632761 and the U.S. Department of Energy Award Number DE-SC0018362.
The diffusion of electrons from ECRIS plasmas results in the emission of bremsstrahlung distributions from the plasma chamber. ECRIS bremsstrahlung measurements that are both time- and energy-resolved are often challenging to perform due to the 10’s; 100’s ms timescale that the plasma evolves over. However, the advancement of low-cost microcontrollers over the last decade makes timing and gating photon spectrometers easier. We present a proof of principle measurement which uses an Arduino microcontroller as a gate-and-delay generator for a High Purity Germanium (HPGe) detector. An example plot of the time-resolved bremsstrahlung spectrum, triggered by beam current variation induced by kinetic instabilities, is shown.

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reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-MOZZO06

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Received ※ 30 September 2020 — Revised ※ 21 October 2020 — Accepted ※ 19 January 2021 — Issue date ※ 23 December 2021

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TUWZO01

Measurements of Plasma Parameters Near Resonance Zones and Peripheral Regions in ECRIS

ECR, dipole, plasma, ECRIS

60

W. Kubo, S. Harisaki, Y. Kato, I. Owada, K. Sato, K. Tsuda
Osaka University, Graduate School of Engineering, Osaka, Japan

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).

Slides TUWZO01 [5.656 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-TUWZO01

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Received ※ 24 September 2020 — Revised ※ 01 October 2020 — Accepted ※ 03 December 2020 — Issue date ※ 16 February 2022

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TUXZO01

A Proposed Explanation of High-Minimum-B Instabilities

resonance, ECR, ion-source, plasma

68

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

It is well-known that electron cyclotron resonance ion sources exhibit instabilities when these sources’ minimum magnetic fields are approximately 80% of the resonant field or greater, but the reasons for this instability have yet to be satisfactorily explained. We show that raising the minimum field makes much faster heating modes accessible at lower energies that invite the onset of kinetic instabilities.

Slides TUXZO01 [3.566 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-TUXZO01

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Received ※ 28 September 2020 — Revised ※ 06 October 2020 — Accepted ※ 03 December 2020 — Issue date ※ 13 December 2020

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TUYZO01

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

plasma, ECR, ECRIS, cyclotron

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]

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

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

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TUYZO02

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

ion-source, plasma, ECR, GUI

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]

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

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

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TUZZO02

Electron Cyclotron Resonance Ion Source Related Research and Development Work at the Department of Physics, University of Jyväskylä (JYFL)

ECR, ECRIS, plasma, ion-source

98

H.A. Koivisto, B.S. Bhaskar, A. Ikonen, T. Kalvas, S.T. Kosonen, R.J. Kronholm, M.S.P. Marttinen, O.P.I. Timonen, V. Toivanen
JYFL, Jyväskylä, Finland
J. Angot, B.S. Bhaskar, T. Thuillier
LPSC, Grenoble Cedex, France
I. Izotov, V. Skalyga
IAP/RAS, Nizhny Novgorod, Russia
L. Maunoury
GANIL, Caen, France
O.A. Tarvainen
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom

Funding: The work has received funding from the Academy of Finland under the Academy of Finland Project funding (No. 315855) and from University Grenoble Alps under EMERGENCE-project.
Recent research work of the JYFL ion source team covers multi-diagnostic studies of plasma instabilities, high-resolution plasma optical emission spectroscopy, ion current transient measurements to define the total life-time of a particle in the highly charged plasma. The JYFL team also elaborates the magnetic and technical design of the unconventional ion source named CUBE. The R&D work includes, in addition, the commissioning and operation of the high-performance 18 GHz ECRIS, HIISI. The instability measurements have revealed new information about the parameters affecting the onset of the plasma instabilities and shown that different instability modes exist. The ion-beam transient studies have given information about the cumulative life-time of highly-charged ions convergent with the ion temperatures deduced from the Doppler broadening of emission lines. The CUBE prototype has a minimum-B quadrupole magnetic field topology, similar to ARC-ECRIS, and its all-permanent magnet structure has been optimized for 10 GHz frequency. The CUBE design will be presented along with its commissioning status. The status and operational experience with HIISI will be reported as well.

Slides TUZZO02 [9.553 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-TUZZO02

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Received ※ 28 September 2020 — Revised ※ 09 November 2020 — Accepted ※ 03 December 2020 — Issue date ※ 05 May 2021

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WEWZO05

Beam Profile Measurements of Decelerated Multicharged Xe Ions from ECRIS for Estimating Low Energy Damage on Satellites Components

radiation, experiment, ECR, ECRIS

125

K. Sato, S. Harisaki, Y. Kato, W. Kubo, K. Okumura, I. Owada, K. Tsuda
Osaka University, Graduate School of Engineering, Osaka, Japan

Electron cyclotron resonance ion source (ECRIS) has been constructed for producing synthesized ion beams in Osaka Univ.*,** Xe is used as fuel for ion propulsion engines on artificial satellites. There are problems of accumulated damages at irradiation and sputtering by low energy Xe ion from the engine. It is required to construct experimentally sputtering yield databases of ion beams in the low energy region from several hundred eV to 1keV, since there are not enough data of satellite component materials. Therefore, we are trying to investigate experimentally sputtering yield on materials by irradiating the low energy single species Xeq+ ion beams. However, there is a problem that if the low extraction voltage, the amount of beam currents is not enough to obtain ion beam flux for precise evaluation of sputtering yield data. Thus, we conduct to decelerate Xeq+ ion beams required low energy region after extracting at high voltage, e.g., 10kV. We measured the decelerated beam profile with x and y direction wire probes. As a result, we were able to estimate the dose of ion fluxes. We are going to conduct irradiation experiments on various materials.
*Y. Kato, et al., RSI, 2014, 85, 02A950-1-3.
**Y. Kato, et al., RSI, 2016, 87, 02A710-1-4.

Slides WEWZO05 [8.964 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEWZO05

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Received ※ 27 September 2020 — Revised ※ 25 September 2020 — Accepted ※ 29 September 2020 — Issue date ※ 14 July 2022

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WEXZO03

Conceptual Design of an Electrostatic Trap for High Intensity Pulsed Beam

ECR, ion-source, simulation, extraction

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]

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

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

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WEYZO02

Design of a 2.45 GHz Surface Wave Plasma Source for Plasma Flood Gun

plasma, ECR, ion-source, coupling

143

S.X. Peng, J.E. Chen, B.J. Cui, Z.Y. Guo, Y.X. Jiang, K. Li, T.H. Ma, J.M. Wen, W.B. Wu, Y. Xu, A.L. Zhang, J.F. Zhang, T. Zhang
PKU, Beijing, People’s Republic of China

Plasma ’ood guns (PFGs) are widely used to neutralize wafer charge during the doping process in modern ion implanters. Compared with traditional dc arc discharge with filament and RF discharge, the microwave driven source that has long lifetime and has no metallic contamination is regarded as a potential choice of PFG [1]. Attempt to develop a large scale PFG based on 2.45 GHz microwave driven sources was launched at Peking University (PKU). A prototype one is a miniaturized 2.45 GHz permanent magnet electron cyclotron resonance (ECR) source to produce point-like electron beam. In previous experiments, more than 8 mA electron beam has been extracted with a ’6 mm extraction hole at an input microwave power of 22 W with argon gas [2]. Recently, studies are focusing on the possibility of producing of ribbon electron beams as PFG with 2.45GHz microwave driven surface wave plasma (SWP) source. A cylindrical chamber surface wave plasma generator with a using cylindrical dielectric waveguide and a 70 mm×3 mm extraction slit was fabricated. The primary test results were obtained. More details of this PFGs will be discussed in this work.
References
[1] B. Vanderberg, et al. AIP Conference Proceedings, 1496(1), 356 (2012).
[2] Yaoxiang Jiang, Shixiang Peng, et al, Review of Scientific Instruments, 91, 033319 (2020).

Slides WEYZO02 [5.475 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEYZO02

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Received ※ 28 September 2020 — Revised ※ 29 December 2020 — Accepted ※ 25 April 2022 — Issue date ※ 14 July 2022

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WEZZO10

Electron Cyclotron Emission Imaging of Electron Cyclotron Resonance Ion Source Plasmas

plasma, ECR, ECRIS, cyclotron

164

L.E. Henderson, H.L. Clark, C.A. Gagliardi
Texas A&M University, Cyclotron Institute, College Station, Texas, USA
D.P. May
Texas A&M University Cyclotron Institute, College Station, Texas, USA

A new imaging system for Electron Cyclotron Resonance Ion Sources (ECRIS) has been designed and is being built. This K- and Ka-band camera will extract localized measurements of absolute energy and relative number density for ECRIS plasma electrons by imaging their Electron Cyclotron Emission (ECE) spectra, as the frequency, shape, and strength of the ECE harmonics correlate directly with the local magnetic field, electron energy, and plasma density. The design of the overall quasi-optical system will be presented, including novel ceramic optics for the radial viewports of the Cyclotron Institute’s ECRIS and metamaterial mirrors with electronically controllable reflectivity. Spatial resolution sufficient to distinguish important plasma regions and temporal resolution sufficient to study dynamic plasma processes is expected.

Slides WEZZO10 [10.583 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEZZO10

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Received ※ 28 September 2020 — Revised ※ 07 October 2020 — Accepted ※ 15 October 2020 — Issue date ※ 16 November 2020

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NACB02

Status of the High-Current EBIS Charge Breeder for the Facility for Rare Isotope Beams

cathode, simulation, gun, space-charge

172

H.J. Son, A.I. Henriques, C. Knowles, A.C.C. Villari
FRIB, East Lansing, Michigan, USA
E.N. Beebe
BNL, Upton, New York, USA
D.B. Crisp, A. Lapierre, S. Nash
NSCL, East Lansing, Michigan, USA

Funding: work supported by the National Science Foundation under Grant No. PHY-1565546
The ReA post-accelerator of the National Supercon-ducting Cyclotron Laboratory (NSCL) at Michigan State University includes an Electron-Beam Ion Trap (EBIT) operating as a charge breeder. The Facility for Rare Iso-tope Beams (FRIB) is being implemented. After comple-tion, rare-isotopes beam rates are expected to exceed in some case 1010 particles per second (pps). The charge capacity of the ReA EBIT is insufficient to handle those rates. Therefore, parts of the TEST EBIS from the Brookhaven National Laboratory (BNL) were transferred to the NSCL to build a High-Current Electron-Beam Ion Source (HCEBIS). The HCEBIS features an electron gun that can provide a current up to 4 A for an estimated trap charge capacity of 1011 elementary charges. This paper presents the HCEBIS specifications, electron-beam cur-rent measurements to test its cathode, and simulation results for its implementation in the ReA post-accelerator. It also presents charge-capacity measurements conducted with the ReA EBIT that demonstrate that the HCEBIS will be able to handle beam rates of more than 1010 pps.

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reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-NACB02

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Received ※ 30 September 2020 — Revised ※ 01 October 2020 — Accepted ※ 30 November 2020 — Issue date ※ 13 March 2021

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NACB03

Determining the Fraction of Extracted 3He in the 3He²⁺ Charge State

simulation, acceleration, collider, rfq

177

M.K. Gronert, E.N. Beebe
BNL, Upton, New York, USA
M.K. Gronert
Drew University, Madison, New Jersey, USA

Funding: Work supported by the US Department of Energy under contract number DE-SC0012704 and by the National Aeronautics and Space Administration
The parameter space of the TOF was explored using analytic methods as well as computer simulation to improve the design and functionality of a similar device that was constructed as a prototype for the Electron Beam Ion Source (EBIS) in 2019. A simulation of the beam line optics was produced in Opera-2D CAD software to show that other optical elements would not materially affect the operation of the TOF. This will allow for true measurements of the charge state ratios of helium for EBIS and extended EBIS operation in support of the Electron Ion Collider. EBIS operators will use the device to maximize the fraction of 3He ions in the 3He²⁺ state. Different geometries were explored as well to maximize the effectiveness of the device and to meet the performance criterion and physical constraints of the EBIS beam line.

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reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-NACB03

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Received ※ 14 October 2020 — Revised ※ 29 October 2020 — Accepted ※ 19 May 2021 — Issue date ※ 19 July 2021

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NACB04

Ion Simulations, Recent Upgrades and Tests with Titan’s Cooler Penning Trap

plasma, simulation, extraction, injection

181

R. Silwal, J. Dilling, B.A. Kootte, A.A. Kwiatkowski, S.F. Paul
TRIUMF, Vancouver, Canada
J. Dilling
UBC & TRIUMF, Vancouver, British Columbia, Canada
G. Gwinner, B.A. Kootte
University of Manitoba, Manitoba, Canada
R. Simpson
UW/Physics, Waterloo, Ontario, Canada

TRIUMF’s Ion Trap for Atomic and Nuclear science (TITAN) facility has the only on-line mass measurement Penning trap (MPET) at a radioactive beam facility that uses an electron beam ion trap (EBIT) to enhance mass precision and resolution. EBITs can charge breed exotic isotopes, making them highly charged, thereby improving the precision of atomic mass measurement as the precision scales linearly with the charge state. However, ion bunches charge bred in the EBIT can have larger energy spread, which poses challenges for mass measurements. A cooler Penning trap (CPET) is currently being developed off-line at TITAN to sympathetically cool the highly charged ions (HCI) with a co-trapped electron plasma, prior to their transport to the MPET. To evaluate the integration of the CPET into the TITAN beamline and to optimize the beam transport, ion trajectory simulations were performed. Hardware upgrades motivated by these simulations and previous test measurements were applied to the off-line CPET setup. Ions and electrons were co-trapped for the first time with the CPET. Progress and challenges on the path towards HCI cooling and integration with the on-line beam facility are presented

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-NACB04

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Received ※ 17 October 2020 — Revised ※ 23 October 2020 — Accepted ※ 01 December 2020 — Issue date ※ 07 February 2021

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