ECRIS2020 - Table of Session: WEWZO (Wednesday Oral Before First Break)

Paper	Title	Page
WEWZO01	Improvement of the Cryostat System Performance of 28-Ghz Electron Cyclotron Resonance Ion Source of the Biba by a Radiation Shielding
	M. Won, J.G. Hong, J.W. Ok, J.Y. Park Korea Basic Science Institute, Busan, Republic of Korea S.J. Kim KBSI, Deajeon, Republic of Korea
	The BIBA (Busan Ion Beam Accelerator) is a compact linear accelerator facility using the 28 GHz ECRIS at the KBSI (Korea Basic Science Institute). Our goal is to generate high current fast neutrons using the heavy ion interaction with a proton target. For a stable operation of the superconducting magnets, the performance of cryostat system is very essential at the 28 GHz ECRIS. However, the emitted x-ray from inner plasma chamber contributes to increase an extra heat load to the cryostat system by absorbing the cold mass of the superconducting magnet. Therefore, we have measured X-ray spectra from the 28 GHz ECR ion source and tried to improve the performance of the Cryostat System by a radiation shielding. In this paper, we will present the test results of X-ray emission on 28GHz KBSI ECRIS and improved cooling system performance.
	Slides WEWZO01 [1.848 MB]
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WEWZO02	Precise Identification of Extracted Ion Beam Spectrum Initially Obtained in Synthesising Iron-Endohedral Fullerenes on ECRIS	114
	I. Owada, S. Harisaki, Y. Kato, W. Kubo, T. Omori, K. Sato, K. Tsuda Osaka University, Graduate School of Engineering, Osaka, Japan A. Kitagawa, M. Muramatsu QST-NIRS, Chiba, Japan Y. Yoshida Toyo University, Kawagoe-shi, Saitama, Japan
	Electron cyclotron resonance ion source (ECRIS) plasma has been constructed for producing synthesized ion beams in Osaka Univ.[1,2] We hope that it can become a universal source capable of producing ions with wide range mass/charge ration (m/q). We have been trying to produce endohedral fullerenes in the ECRIS. We have conducted initial experiments on production of them only in the second stage of ECRIS. We have been using iron vapor source by induction heating (IH) from the mirror end along to the geometrical axis, and C60 crucible from the side wall, respectively. We succeeded in realizing ECR plasma that fullerene and iron ions coexist on the single stage ECRIS, even by 1kV extraction voltage.[3] By these experimental series, the typical CSD suggests that there is possibility of slight formation of iron fullerenes compounds and iron endohedral fullerenes. We are continuing to investigate the experimental conditions that maximize spectrum corresponding to iron endohedral fullerenes. In this paper we describe preliminary experimental results of synthesizing iron-endohedral fullerene on the ECRIS. Y. Kato, et al., RSI, 2014, 85, 02A950-1-3. Y. Kato, et al., RSI, 2016, 87, 02A710-1-4. **Y. Kato, et.al., IIT2018, IEEE Conf. Publ., 2019, pp.172-175.
	Slides WEWZO02 [1.932 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEWZO02
About •	Received ※ 25 September 2020 — Revised ※ 14 October 2020 — Accepted ※ 03 November 2020 — Issue date ※ 12 January 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEWZO03	High Intensity Vanadium Beam Production to Search for New Super-Heavy Element with Z = 119	118
	T. Nagatomo, Y. Higurashi, O. Kamigaito, T. Nakagawa, J. Ohnishi RIKEN Nishina Center, Wako, Japan
	We have begun searching for the new super-heavy element (SHE) with Z=119 at RIKEN Heavy Ion LINAC (RILAC). To overcome the small production cross section of vanadium (V) beam on the curium target, the project requires a very powerful V beam. In order to optimize the beam intensity of V with the charge state of 13+, we have investigated the effects of the amount of V vapor, the power of 18- and 28-GHz microwaves, and the strength of the mirror field. While no significant effect was seen by changing the mirror field Bext from 1.4 T to 1.6 T, the amount of V vapor and the microwave power strongly affected. Based on the correlation between the V-vapor and the microwave power, we obtained a 600-euA V(13+) beam with the V consumption rate of 24 mg/h and the microwave power of 2.9 kW in order to execute about 1-month SHE experiment. Furthermore, because such strong mirror field enhances the transverse beam emittance, it is important to control the emittance with small reduction of the intensity. We have successfully controlled the beam emittance by using three pairs of slits (triplet slits) in LEBT by eliminating the peripheral beam components in both of the x-x’ and y-y’ phase spaces.
	Slides WEWZO03 [2.981 MB]
	Poster WEWZO03 [13.283 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEWZO03
About •	Received ※ 28 September 2020 — Revised ※ 29 October 2020 — Accepted ※ 22 January 2021 — Issue date ※ 18 May 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEWZO04	Producing Multicharged Ions by Pulse Modulated Microwaves at Mixing Low Z Gases on ECRIS	122
	S. Harisaki, Y. Kato, W. Kubo, I. Owada, K. Sato, K. Tsuda Osaka University, Graduate School of Engineering, Osaka, Japan
	We are aiming at producing various ion beams in ECRIS. In the case of producing multicharged ion beams, we try to enhance loss channel of low Z ions by means of adding pulse modulated microwaves to conventional gas mixing method.* Through these experiments, we explore the feasibility of selectively heating specific ions with pulse modulated microwaves and launching another low frequency RF waves. In gas mixing experiment, we use Helium as low Z gas for production of multicharged Ar and Xenon ion beams. These experiments are conducted by keeping the total pressure constant and changing the mixing ratio of Helium. The time scale of pulsed microwave is typically several to several hundreds of microseconds. We optimize the pulse period and duty ratio for producing multicharged ion beams. These effects are investigated to measure Charge State Distributions (CSDs). Also, we can measure the emittance using wire probe and multi slit attached to Ion Beam Irradiation System (IBIS). ** We estimate the normalized emittance from this measurement to determine index of ion temperature in the ECRIS. In this paper, we mainly describe the results of these active and additive methods at the ECRIS. M. Muramatsu, et al., Review of Scientific Instruments, 87, 02C110(2016). *K. Okumura, et al., Review of Scientific Instruments, 91, 023311(2020).
	Slides WEWZO04 [1.283 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEWZO04
About •	Received ※ 24 September 2020 — Revised ※ 27 September 2020 — Accepted ※ 03 December 2020 — Issue date ※ 15 July 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEWZO05	Beam Profile Measurements of Decelerated Multicharged Xe Ions from ECRIS for Estimating Low Energy Damage on Satellites Components	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
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEWZO06	Observation of Cyclotron Instabilities in SECRAL-II Ion Source
	L.X. Li, Y.C. Feng, J.W. Guo, D. Hitz, J.B. Li, W. Lu, L.T. Sun, W.H. Zhang, X.Z. Zhang, H.W. Zhao IMP/CAS, Lanzhou, People’s Republic of China
	Cyclotron instabilities in Electron Cyclotron Resonance Ion Source (ECRIS) plasmas are related to non-linear interaction between plasma waves and energetic electrons, resulting in strong microwave emission, a burst of energetic electrons escaping the plasma, and the periodic oscillations of the extracted beam currents. Precedent investigation of cyclotron instabilities has proved that Bmin/BECR can be treated as a magnetic field threshold. Recently, experiments with SECRAL-II ion source demonstrate that Bmin/BECR is not the only knob, and other field parameters have also been found to be related to cyclotron instabilities, such as mirror ratio and radial field. Namely, the trigger of cyclotron instability is a combination of many magnetic field parameters. This paper will give the experimental setup at IMP for cyclotron instability investigations and experimental observations will be presented.
	Slides WEWZO06 [1.021 MB]
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

WEWZO01

Improvement of the Cryostat System Performance of 28-Ghz Electron Cyclotron Resonance Ion Source of the Biba by a Radiation Shielding

M. Won, J.G. Hong, J.W. Ok, J.Y. Park
Korea Basic Science Institute, Busan, Republic of Korea
S.J. Kim
KBSI, Deajeon, Republic of Korea

The BIBA (Busan Ion Beam Accelerator) is a compact linear accelerator facility using the 28 GHz ECRIS at the KBSI (Korea Basic Science Institute). Our goal is to generate high current fast neutrons using the heavy ion interaction with a proton target. For a stable operation of the superconducting magnets, the performance of cryostat system is very essential at the 28 GHz ECRIS. However, the emitted x-ray from inner plasma chamber contributes to increase an extra heat load to the cryostat system by absorbing the cold mass of the superconducting magnet. Therefore, we have measured X-ray spectra from the 28 GHz ECR ion source and tried to improve the performance of the Cryostat System by a radiation shielding. In this paper, we will present the test results of X-ray emission on 28GHz KBSI ECRIS and improved cooling system performance.

Slides WEWZO01 [1.848 MB]

Cite •

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

WEWZO02

Precise Identification of Extracted Ion Beam Spectrum Initially Obtained in Synthesising Iron-Endohedral Fullerenes on ECRIS

114

I. Owada, S. Harisaki, Y. Kato, W. Kubo, T. Omori, K. Sato, K. Tsuda
Osaka University, Graduate School of Engineering, Osaka, Japan
A. Kitagawa, M. Muramatsu
QST-NIRS, Chiba, Japan
Y. Yoshida
Toyo University, Kawagoe-shi, Saitama, Japan

Electron cyclotron resonance ion source (ECRIS) plasma has been constructed for producing synthesized ion beams in Osaka Univ.[1,2] We hope that it can become a universal source capable of producing ions with wide range mass/charge ration (m/q). We have been trying to produce endohedral fullerenes in the ECRIS. We have conducted initial experiments on production of them only in the second stage of ECRIS. We have been using iron vapor source by induction heating (IH) from the mirror end along to the geometrical axis, and C60 crucible from the side wall, respectively. We succeeded in realizing ECR plasma that fullerene and iron ions coexist on the single stage ECRIS, even by 1kV extraction voltage.[3] By these experimental series, the typical CSD suggests that there is possibility of slight formation of iron fullerenes compounds and iron endohedral fullerenes. We are continuing to investigate the experimental conditions that maximize spectrum corresponding to iron endohedral fullerenes. In this paper we describe preliminary experimental results of synthesizing iron-endohedral fullerene on the ECRIS.
*Y. Kato, et al., RSI, 2014, 85, 02A950-1-3.
**Y. Kato, et al., RSI, 2016, 87, 02A710-1-4.
***Y. Kato, et.al., IIT2018, IEEE Conf. Publ., 2019, pp.172-175.

Slides WEWZO02 [1.932 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEWZO02

About •

Received ※ 25 September 2020 — Revised ※ 14 October 2020 — Accepted ※ 03 November 2020 — Issue date ※ 12 January 2022

Cite •

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

WEWZO03

High Intensity Vanadium Beam Production to Search for New Super-Heavy Element with Z = 119

118

T. Nagatomo, Y. Higurashi, O. Kamigaito, T. Nakagawa, J. Ohnishi
RIKEN Nishina Center, Wako, Japan

We have begun searching for the new super-heavy element (SHE) with Z=119 at RIKEN Heavy Ion LINAC (RILAC). To overcome the small production cross section of vanadium (V) beam on the curium target, the project requires a very powerful V beam. In order to optimize the beam intensity of V with the charge state of 13+, we have investigated the effects of the amount of V vapor, the power of 18- and 28-GHz microwaves, and the strength of the mirror field. While no significant effect was seen by changing the mirror field Bext from 1.4 T to 1.6 T, the amount of V vapor and the microwave power strongly affected. Based on the correlation between the V-vapor and the microwave power, we obtained a 600-euA V(13+) beam with the V consumption rate of 24 mg/h and the microwave power of 2.9 kW in order to execute about 1-month SHE experiment. Furthermore, because such strong mirror field enhances the transverse beam emittance, it is important to control the emittance with small reduction of the intensity. We have successfully controlled the beam emittance by using three pairs of slits (triplet slits) in LEBT by eliminating the peripheral beam components in both of the x-x’ and y-y’ phase spaces.

Slides WEWZO03 [2.981 MB]

Poster WEWZO03 [13.283 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEWZO03

About •

Received ※ 28 September 2020 — Revised ※ 29 October 2020 — Accepted ※ 22 January 2021 — Issue date ※ 18 May 2021

Cite •

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

WEWZO04

Producing Multicharged Ions by Pulse Modulated Microwaves at Mixing Low Z Gases on ECRIS

122

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

We are aiming at producing various ion beams in ECRIS. In the case of producing multicharged ion beams, we try to enhance loss channel of low Z ions by means of adding pulse modulated microwaves to conventional gas mixing method.* Through these experiments, we explore the feasibility of selectively heating specific ions with pulse modulated microwaves and launching another low frequency RF waves. In gas mixing experiment, we use Helium as low Z gas for production of multicharged Ar and Xenon ion beams. These experiments are conducted by keeping the total pressure constant and changing the mixing ratio of Helium. The time scale of pulsed microwave is typically several to several hundreds of microseconds. We optimize the pulse period and duty ratio for producing multicharged ion beams. These effects are investigated to measure Charge State Distributions (CSDs). Also, we can measure the emittance using wire probe and multi slit attached to Ion Beam Irradiation System (IBIS). ** We estimate the normalized emittance from this measurement to determine index of ion temperature in the ECRIS. In this paper, we mainly describe the results of these active and additive methods at the ECRIS.
*M. Muramatsu, et al., Review of Scientific Instruments, 87, 02C110(2016).
**K. Okumura, et al., Review of Scientific Instruments, 91, 023311(2020).

Slides WEWZO04 [1.283 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ECRIS2020-WEWZO04

About •

Received ※ 24 September 2020 — Revised ※ 27 September 2020 — Accepted ※ 03 December 2020 — Issue date ※ 15 July 2021

Cite •

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

WEWZO05

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

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

Cite •

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

WEWZO06

Observation of Cyclotron Instabilities in SECRAL-II Ion Source

L.X. Li, Y.C. Feng, J.W. Guo, D. Hitz, J.B. Li, W. Lu, L.T. Sun, W.H. Zhang, X.Z. Zhang, H.W. Zhao
IMP/CAS, Lanzhou, People’s Republic of China

Cyclotron instabilities in Electron Cyclotron Resonance Ion Source (ECRIS) plasmas are related to non-linear interaction between plasma waves and energetic electrons, resulting in strong microwave emission, a burst of energetic electrons escaping the plasma, and the periodic oscillations of the extracted beam currents. Precedent investigation of cyclotron instabilities has proved that Bmin/BECR can be treated as a magnetic field threshold. Recently, experiments with SECRAL-II ion source demonstrate that Bmin/BECR is not the only knob, and other field parameters have also been found to be related to cyclotron instabilities, such as mirror ratio and radial field. Namely, the trigger of cyclotron instability is a combination of many magnetic field parameters. This paper will give the experimental setup at IMP for cyclotron instability investigations and experimental observations will be presented.

Slides WEWZO06 [1.021 MB]

Cite •

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