Cyclotrons2019 - List of Authors (Lee, J.C.)

Paper	Title	Page
MOP028	Design of 5.8 MHz RF Electrode for AMS Cyclotron	94
	D.H. Ha, J.-S. Chai, Kh.M. Gad, M. Ghergherehchi, H.S. Kim, J.C. Lee, H. Namgoong SKKU, Suwon, Republic of Korea
	Accelerator Mass Spectrometry (AMS) is a powerful method for separating isotopes, and electrostatic tandem accelerators are widely used for AMS. Sungkyunkwan University is developing AMS that can be used in a smaller space based on cyclotron. Unlike conventional cyclotrons used in PET or proton therapy, cyclotron-based AMS provides high turn number and high resolution. In this study, we proposed a cavity with a frequency of 5.8 MHz and an accelerating voltage of 300 V to accelerate the particles in the cyclotron. The proposed cavity was designed as an electrode and verified by CST Microwave studio.
	Poster MOP028 [1.078 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-Cyclotrons2019-MOP028
About •	paper received ※ 15 September 2019 paper accepted ※ 24 September 2019 issue date ※ 20 June 2020
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOP029	Design and Manufacture of 10 kW, 83.2 MHz 4-way Power Combiner for Solid State Amplifier	97
	D.H. Ha, J.-S. Chai, Kh.M. Gad, M. Ghergherehchi, H.S. Kim, J.C. Lee, H. Namgoong SKKU, Suwon, Republic of Korea
	The purpose of this study is to improve the insertion loss of a 20 kW solid-state RF power amplifier and the power coupling efficiency by reducing reflected power. For this purpose, a power combiner, which is a core component of a solid-state RF power amplifier, was designed and fabricated. The 4-way power combiner employs the Wilkinson type, which has excellent power coupling efficiency and isolation, and operates at 83.2 MHz. This paper covers the design and cold test results.
	Poster MOP029 [1.396 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-Cyclotrons2019-MOP029
About •	paper received ※ 15 September 2019 paper accepted ※ 26 September 2019 issue date ※ 20 June 2020
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOP030	RF measurement of SKKUCY-10 RF Cavity for Impedance Matching	100
	J.C. Lee, J.-S. Chai, Kh.M. Gad, M. Ghergherehchi, D.H. Ha, H.S. Kim, H. Namgoong SKKU, Suwon, Republic of Korea
	Funding: Radiation Technology R&D program through the National Research Foundation of Korea funded by the Ministry of Science, ICT & Future Planning through the National Research Foundation of Korea The 10 MeV cyclotron was designed for next version in Sungkyunkwan University, after the SKKUCY-9 had developed for medical application for PET. The RF cavity, which generates the electric field in cyclotron, was designed based on a half-wavelength resonator and optimized to improve the unloaded quality factor (Q₀). The design specifications of RF cavity were resonance frequency 83.2 MHz, Q₀ 5830 and Dee voltage 40 kV with geometrical values resonator length 560 mm, Dee angle 35° and Stem radius 16 mm. The RF cavity of the SKKUCY-10 was fabricated and installed inside the electromagnet, and RF characteristics were measured with a network analyzer. The RF coupling coefficient and characteristic impedance for desired condition were selected at 1.08 and 52 ’, respectively. The RF coupling coefficient and characteristic impedance were measured 0.8-1.2, 52-49 ’ according to temperature as 15-21°C. The power coupler was checked for optimization of RF coupling coefficient and characteristic impedance, and the results show good agreement with simulated and measured data.
	Poster MOP030 [1.665 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-Cyclotrons2019-MOP030
About •	paper received ※ 15 September 2019 paper accepted ※ 23 June 2020 issue date ※ 20 June 2020
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOP031	Design of High Sensitive Magnet and Beam Dynamics for AMS Cyclotron	103
	H. Namgoong, J.-S. Chai, M. Ghergherehchi, D.H. Ha, H.S. Kim, J.C. Lee SKKU, Suwon, Republic of Korea
	To produce a carbon-14 for Accelerator Mass Spectrometry (AMS), AMS Cyclotron magnet was designed. For the AMS system, Cyclotron magnet has been required high mass resolution. In order to realize high mass resolution, the phase error is designed within ±10 and the mass resolution was 5000. We used CST particle studio and Cyclone for beam dynamics simulation of this cyclotron magnet. This paper describes the AMS cyclotron magnet and beam dynamics design.
	Poster MOP031 [2.281 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-Cyclotrons2019-MOP031
About •	paper received ※ 15 September 2019 paper accepted ※ 24 September 2019 issue date ※ 20 June 2020
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP030	Reinforcement Learning Based RF Control System for Accelerator Mass Spectrometry	227
	H.S. Kim, J.-S. Chai, Kh.M. Gad, M. Ghergherehchi, D.H. Ha, J.C. Lee, H. Namgoong SKKU, Suwon, Republic of Korea
	Funding: Radiation Technology R&D program through the National Research Foundation of Korea funded by the Ministry of Science, ICT & Future Planning through the National Research Foundation of Korea Accelerator Mass Spectrometry (AMS) is a powerful method for separating rare isotopes and electrostatic type tandem accelerators have been widely used. At SungKyunKwan University, we are developing a AMS that can be used in a small space with higher resolution based on cyclotron. In contrast to the cyclotron used in conventional PET or proton therapy, the cyclotron-based AMS is characterized by high turn number and low dee voltage for high resolution. It is designed to accelerate not only 14C but also 13C or 12C. The AMS cyclotron RF control model has nonlinear characteristics due to the variable beam loading effect due to the acceleration of various particles and injected sample amounts. In this work, we proposed an AMS control system based on reinforcement learning. The proposed reinforcement learning finds the target control value in response to the environment through the learning process. We have designed a reinforcement learning based controller with RF system as an environment and verified the reinforcement learning based controller designed through the modeled cavity.
	Poster TUP030 [0.527 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-Cyclotrons2019-TUP030
About •	paper received ※ 14 September 2019 paper accepted ※ 25 September 2019 issue date ※ 20 June 2020
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THC03	Design of Accelerator Mass Spectrometry Based on a Cyclotron	314
	H. Namgoong, J.-S. Chai, M. Ghergherehchi, D.H. Ha, H.S. Kim, J.C. Lee SKKU, Suwon, Republic of Korea
	In this paper, we present a cyclotron-based accelerator mass spectrometry system. Conventional AMS systems use tandem accelerators for generating carbon-14 beams. We have developed an ion source, RF buncher, cyclotron, triplet quadrupole, detector and dipole magnet for an AMS system.
	Slides THC03 [9.741 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-Cyclotrons2019-THC03
About •	paper received ※ 15 September 2019 paper accepted ※ 26 September 2019 issue date ※ 20 June 2020
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Design of 5.8 MHz RF Electrode for AMS Cyclotron

94

D.H. Ha, J.-S. Chai, Kh.M. Gad, M. Ghergherehchi, H.S. Kim, J.C. Lee, H. Namgoong
SKKU, Suwon, Republic of Korea

Accelerator Mass Spectrometry (AMS) is a powerful method for separating isotopes, and electrostatic tandem accelerators are widely used for AMS. Sungkyunkwan University is developing AMS that can be used in a smaller space based on cyclotron. Unlike conventional cyclotrons used in PET or proton therapy, cyclotron-based AMS provides high turn number and high resolution. In this study, we proposed a cavity with a frequency of 5.8 MHz and an accelerating voltage of 300 V to accelerate the particles in the cyclotron. The proposed cavity was designed as an electrode and verified by CST Microwave studio.

Poster MOP028 [1.078 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-Cyclotrons2019-MOP028

About •

paper received ※ 15 September 2019 paper accepted ※ 24 September 2019 issue date ※ 20 June 2020

Export •

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

MOP029

Design and Manufacture of 10 kW, 83.2 MHz 4-way Power Combiner for Solid State Amplifier

97

D.H. Ha, J.-S. Chai, Kh.M. Gad, M. Ghergherehchi, H.S. Kim, J.C. Lee, H. Namgoong
SKKU, Suwon, Republic of Korea

The purpose of this study is to improve the insertion loss of a 20 kW solid-state RF power amplifier and the power coupling efficiency by reducing reflected power. For this purpose, a power combiner, which is a core component of a solid-state RF power amplifier, was designed and fabricated. The 4-way power combiner employs the Wilkinson type, which has excellent power coupling efficiency and isolation, and operates at 83.2 MHz. This paper covers the design and cold test results.

Poster MOP029 [1.396 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-Cyclotrons2019-MOP029

About •

paper received ※ 15 September 2019 paper accepted ※ 26 September 2019 issue date ※ 20 June 2020

Export •

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

MOP030

RF measurement of SKKUCY-10 RF Cavity for Impedance Matching

100

J.C. Lee, J.-S. Chai, Kh.M. Gad, M. Ghergherehchi, D.H. Ha, H.S. Kim, H. Namgoong
SKKU, Suwon, Republic of Korea

Funding: Radiation Technology R&D program through the National Research Foundation of Korea funded by the Ministry of Science, ICT & Future Planning through the National Research Foundation of Korea
The 10 MeV cyclotron was designed for next version in Sungkyunkwan University, after the SKKUCY-9 had developed for medical application for PET. The RF cavity, which generates the electric field in cyclotron, was designed based on a half-wavelength resonator and optimized to improve the unloaded quality factor (Q₀). The design specifications of RF cavity were resonance frequency 83.2 MHz, Q₀ 5830 and Dee voltage 40 kV with geometrical values resonator length 560 mm, Dee angle 35° and Stem radius 16 mm. The RF cavity of the SKKUCY-10 was fabricated and installed inside the electromagnet, and RF characteristics were measured with a network analyzer. The RF coupling coefficient and characteristic impedance for desired condition were selected at 1.08 and 52 ’, respectively. The RF coupling coefficient and characteristic impedance were measured 0.8-1.2, 52-49 ’ according to temperature as 15-21°C. The power coupler was checked for optimization of RF coupling coefficient and characteristic impedance, and the results show good agreement with simulated and measured data.

Poster MOP030 [1.665 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-Cyclotrons2019-MOP030

About •

paper received ※ 15 September 2019 paper accepted ※ 23 June 2020 issue date ※ 20 June 2020

Export •

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

MOP031

Design of High Sensitive Magnet and Beam Dynamics for AMS Cyclotron

103

H. Namgoong, J.-S. Chai, M. Ghergherehchi, D.H. Ha, H.S. Kim, J.C. Lee
SKKU, Suwon, Republic of Korea

To produce a carbon-14 for Accelerator Mass Spectrometry (AMS), AMS Cyclotron magnet was designed. For the AMS system, Cyclotron magnet has been required high mass resolution. In order to realize high mass resolution, the phase error is designed within ±10 and the mass resolution was 5000. We used CST particle studio and Cyclone for beam dynamics simulation of this cyclotron magnet. This paper describes the AMS cyclotron magnet and beam dynamics design.

Poster MOP031 [2.281 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-Cyclotrons2019-MOP031

About •

paper received ※ 15 September 2019 paper accepted ※ 24 September 2019 issue date ※ 20 June 2020

Export •

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

TUP030

Reinforcement Learning Based RF Control System for Accelerator Mass Spectrometry

227

H.S. Kim, J.-S. Chai, Kh.M. Gad, M. Ghergherehchi, D.H. Ha, J.C. Lee, H. Namgoong
SKKU, Suwon, Republic of Korea

Funding: Radiation Technology R&D program through the National Research Foundation of Korea funded by the Ministry of Science, ICT & Future Planning through the National Research Foundation of Korea
Accelerator Mass Spectrometry (AMS) is a powerful method for separating rare isotopes and electrostatic type tandem accelerators have been widely used. At SungKyunKwan University, we are developing a AMS that can be used in a small space with higher resolution based on cyclotron. In contrast to the cyclotron used in conventional PET or proton therapy, the cyclotron-based AMS is characterized by high turn number and low dee voltage for high resolution. It is designed to accelerate not only 14C but also 13C or 12C. The AMS cyclotron RF control model has nonlinear characteristics due to the variable beam loading effect due to the acceleration of various particles and injected sample amounts. In this work, we proposed an AMS control system based on reinforcement learning. The proposed reinforcement learning finds the target control value in response to the environment through the learning process. We have designed a reinforcement learning based controller with RF system as an environment and verified the reinforcement learning based controller designed through the modeled cavity.

Poster TUP030 [0.527 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-Cyclotrons2019-TUP030

About •

paper received ※ 14 September 2019 paper accepted ※ 25 September 2019 issue date ※ 20 June 2020

Export •

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

THC03

Design of Accelerator Mass Spectrometry Based on a Cyclotron

314

H. Namgoong, J.-S. Chai, M. Ghergherehchi, D.H. Ha, H.S. Kim, J.C. Lee
SKKU, Suwon, Republic of Korea

In this paper, we present a cyclotron-based accelerator mass spectrometry system. Conventional AMS systems use tandem accelerators for generating carbon-14 beams. We have developed an ion source, RF buncher, cyclotron, triplet quadrupole, detector and dipole magnet for an AMS system.

Slides THC03 [9.741 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-Cyclotrons2019-THC03

About •

paper received ※ 15 September 2019 paper accepted ※ 26 September 2019 issue date ※ 20 June 2020

Export •

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