IPAC2014 - List of Authors (Kim, H.J.)

Paper	Title	Page
WEOBA02	Superconducting Linac for Rare Isotope Science Project	1861
	H.J. Kim, H.J. Cha, M.O. Hyun, H. Jang, H.C. Jung, Y. Kim, M. Lee, G.-T. Park IBS, Daejeon, Republic of Korea
	Rare Isotope Science Project (RISP) has been proposed as a multi-purpose accelerator facility for providing beams of exotic rare isotopes of various energies. The RISP driver linac which is used to accelerate the beam, for an example, Uranium ions from 0.5 MeV/u to 200 MeV/u consists of superconducting RF cavities and warm quadrupole magnets for focusing heavy ion beams. Requirement of the linac design is especially high for acceleration of multiple charge beams. In this paper, we present the status of RISP linac design and the development of superconducting cavity and cryomodule.
	Slides WEOBA02 [9.226 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEOBA02
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPRI034	Analysis of BCP Characteristics for SRF Cavities	2549
	Y. Jung, H.J. Kim IBS, Daejeon, Republic of Korea H.H. Lee, H.C. Yang KRICT, Daejoen, Republic of Korea
	A chemical polishing process is well-known critical process for improving superconducting cavities such as a quality factor and an acceleration electric filed with additional temperature treatment. Especially, Buffered Chemical Polishing (BCP) has been widely used in SRF (Superconducting Radio Frequency) cavity processing. We performed BCP experiments with 1:1:1 and 1:1:2 of an etchant ratio (HF:HNO3:H3PO4). In fact, BCP experiments were carried out by using both undeformed (as-receoved) and deformed niobium samples. We will report baseline BCP results by analyzing surface states of niobium samples such as optical photographs, etch rates and AFM (Atomic Force Microscopy) depending on temperature and time.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRI034
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPRI035	Stiffening Structure of the HWR at RISP	2552
	G.-T. Park, H.J. Cha, H. Kim, H.J. Kim, W.K. Kim IBS, Daejeon, Republic of Korea
	The HWR being developed in RISP, Korea is in its final stage of the design. We consider the effects of the stiffeners in the presence of the helium vessel on the various detunings such as cool down, helium pressure fluctuation, Lorentz pressure. The interaction of the stiffened cavity with the helium jacket is studied via the coupled simulation by ANSYS and the optimal specification of the stiffeners are determined. In addition, the expected frequency shift is predicted to establish the target frequency bfor the manufacturing. The effect of the vibrational motion is also studied.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRI035
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPRI036	Fabrication Design of QWR and HWR Cryomodules	2555
	W.K. Kim, H. Kim, H.J. Kim, Y. Kim, M. Lee, G.-T. Park IBS, Daejeon, Republic of Korea
	The superconducting linac of RAON consists of five types of cryomodules. The cryomodules host QWR, HWR1, HWR2, SSR1, and SSR2 superconducting cavities. The cryomodules will be operated at 2K in order to test the performance of the superconducting cavities. The design of the cryomodule components is based on thermal shield to prevent incoming heat, two-phase pipe to supply superfluid helium, vacuum vessel for the formation of the internal vacuum, supporter parts for alignment and keeping structure, and magnetic shield to prevent external magnetic field. The detailed fabrication design of the cryomodules will be presented in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRI036
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPRI106	Design of Cryomoudles for RAON	2746
	Y. Kim, C. Choi, H.M. Jang, Y.W. Jo, H.J. Kim, W.K. Kim, M. Lee IBS, Daejeon, Republic of Korea
	The accelerator will be built in Korea called RAON has four kinds of superconducting cavities such as QWR, HWR1, SSR1 and SSR2, and those cavities are operating in 2 K. The fabrication design for the SSR1 and SSR2 cryomodules are reported in this paper. The issues included in the paper are thermal and structural analysis results for the components such thermal shield, support post, two phase pipe, and so on.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRI106
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPME148	Beam Dynamics Issues for a Superconducting Linear Accelerator-based High Power Heavy Ion Machine	3602
SUSPSNE038	use link to see paper's listing under its alternate paper code
	J.G. Hwang, E.-S. Kim Kyungpook National University, Daegu, Republic of Korea H. Jang, D. Jeon, H.J. Kim, H.J. Kim IBS, Daejeon, Republic of Korea
	The driver linac of RAON heavy ion accelerator based on the superconducting technology, which consists of a 28 GHz ECR ion source, a low energy beam transport line, a RFQ accelerator, a medium energy beam transport line, a low energy linac(SCL1), a charge stripping section and a high energy linac(SCL2), will produce the stable ion beam from proton with 600 MeV to uranium with 200 MeV/u. Many beam dynamics issues such as beam steering effect due to QWR cavities with the peak electric field of 35 MV/m, emittance growth in charge stripper due to the straggling effect, parametric resonance and envelope instability were verified to design the high power heavy ion machine which can produce the high quality beam. In this presentation, we explain our study results for achieving longitudinal acceptance larger than 27 keV/u-ns for the stable operation and minimizing the emittance growth less than 30 % in the superconducting linac for high quality beam at the in-flight target.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME148
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPME149	Beam Dynamics Issues in the Post Accelerator for the Rare Isotope Ion Beams from ISOL System in RISP	3605
	J.G. Hwang, S.W. Jang, E.-S. Kim Kyungpook National University, Daegu, Republic of Korea B.H. Choi, D. Jeon, H.J. Kim, H.J. Kim, I. Shin IBS, Daejeon, Republic of Korea L. Lee KNU, Deagu, Republic of Korea
	The accelerator for RISP, which is the superconducting technology based heavy ion linear accelerator construction project, is composed mainly of the driver linac for stable ion beam from an ECR ion source and post linac for unstable ion from an ISOL system. The post accelerator can accelerate the unstable ion beams up to 16.5 MeV/u for 132Sn and 16.0 MeV/u for 58Ni, which has the ratio of mass to charge, A/q, of 8.3. The unstable ion beam such as 132Sn from an ISOL system has the large transverse and longitudinal emittances. Hence acceptance and envelope of the post accelerator should optimize for stable operation. The beam was transported by the post-to-driver transport (P2DT) line which consists of a charge stripper, two charge selection sections and a telescope section with the bunching cavities. In this presentation, we will show the criteria for the design of the post accelerator and result of beam tracking simulation from the low energy transport line to the end of post linac. The initial coordinates of the particles were acquired by the tracking simulation from the low energy beam transport (LEBT) line to the medium energy beam transport (MEBT) line.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME149
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Superconducting Linac for Rare Isotope Science Project

1861

H.J. Kim, H.J. Cha, M.O. Hyun, H. Jang, H.C. Jung, Y. Kim, M. Lee, G.-T. Park
IBS, Daejeon, Republic of Korea

Rare Isotope Science Project (RISP) has been proposed as a multi-purpose accelerator facility for providing beams of exotic rare isotopes of various energies. The RISP driver linac which is used to accelerate the beam, for an example, Uranium ions from 0.5 MeV/u to 200 MeV/u consists of superconducting RF cavities and warm quadrupole magnets for focusing heavy ion beams. Requirement of the linac design is especially high for acceleration of multiple charge beams. In this paper, we present the status of RISP linac design and the development of superconducting cavity and cryomodule.

Slides WEOBA02 [9.226 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEOBA02

Export •

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

WEPRI034

Analysis of BCP Characteristics for SRF Cavities

2549

Y. Jung, H.J. Kim
IBS, Daejeon, Republic of Korea
H.H. Lee, H.C. Yang
KRICT, Daejoen, Republic of Korea

A chemical polishing process is well-known critical process for improving superconducting cavities such as a quality factor and an acceleration electric filed with additional temperature treatment. Especially, Buffered Chemical Polishing (BCP) has been widely used in SRF (Superconducting Radio Frequency) cavity processing. We performed BCP experiments with 1:1:1 and 1:1:2 of an etchant ratio (HF:HNO3:H3PO4). In fact, BCP experiments were carried out by using both undeformed (as-receoved) and deformed niobium samples. We will report baseline BCP results by analyzing surface states of niobium samples such as optical photographs, etch rates and AFM (Atomic Force Microscopy) depending on temperature and time.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRI034

Export •

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

WEPRI035

Stiffening Structure of the HWR at RISP

2552

G.-T. Park, H.J. Cha, H. Kim, H.J. Kim, W.K. Kim
IBS, Daejeon, Republic of Korea

The HWR being developed in RISP, Korea is in its final stage of the design. We consider the effects of the stiffeners in the presence of the helium vessel on the various detunings such as cool down, helium pressure fluctuation, Lorentz pressure. The interaction of the stiffened cavity with the helium jacket is studied via the coupled simulation by ANSYS and the optimal specification of the stiffeners are determined. In addition, the expected frequency shift is predicted to establish the target frequency bfor the manufacturing. The effect of the vibrational motion is also studied.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRI035

Export •

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

WEPRI036

Fabrication Design of QWR and HWR Cryomodules

2555

W.K. Kim, H. Kim, H.J. Kim, Y. Kim, M. Lee, G.-T. Park
IBS, Daejeon, Republic of Korea

The superconducting linac of RAON consists of five types of cryomodules. The cryomodules host QWR, HWR1, HWR2, SSR1, and SSR2 superconducting cavities. The cryomodules will be operated at 2K in order to test the performance of the superconducting cavities. The design of the cryomodule components is based on thermal shield to prevent incoming heat, two-phase pipe to supply superfluid helium, vacuum vessel for the formation of the internal vacuum, supporter parts for alignment and keeping structure, and magnetic shield to prevent external magnetic field. The detailed fabrication design of the cryomodules will be presented in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRI036

Export •

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

WEPRI106

Design of Cryomoudles for RAON

2746

Y. Kim, C. Choi, H.M. Jang, Y.W. Jo, H.J. Kim, W.K. Kim, M. Lee
IBS, Daejeon, Republic of Korea

The accelerator will be built in Korea called RAON has four kinds of superconducting cavities such as QWR, HWR1, SSR1 and SSR2, and those cavities are operating in 2 K. The fabrication design for the SSR1 and SSR2 cryomodules are reported in this paper. The issues included in the paper are thermal and structural analysis results for the components such thermal shield, support post, two phase pipe, and so on.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRI106

Export •

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

THPME148

Beam Dynamics Issues for a Superconducting Linear Accelerator-based High Power Heavy Ion Machine

3602

SUSPSNE038

use link to see paper's listing under its alternate paper code

J.G. Hwang, E.-S. Kim
Kyungpook National University, Daegu, Republic of Korea
H. Jang, D. Jeon, H.J. Kim, H.J. Kim
IBS, Daejeon, Republic of Korea

The driver linac of RAON heavy ion accelerator based on the superconducting technology, which consists of a 28 GHz ECR ion source, a low energy beam transport line, a RFQ accelerator, a medium energy beam transport line, a low energy linac(SCL1), a charge stripping section and a high energy linac(SCL2), will produce the stable ion beam from proton with 600 MeV to uranium with 200 MeV/u. Many beam dynamics issues such as beam steering effect due to QWR cavities with the peak electric field of 35 MV/m, emittance growth in charge stripper due to the straggling effect, parametric resonance and envelope instability were verified to design the high power heavy ion machine which can produce the high quality beam. In this presentation, we explain our study results for achieving longitudinal acceptance larger than 27 keV/u-ns for the stable operation and minimizing the emittance growth less than 30 % in the superconducting linac for high quality beam at the in-flight target.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME148

Export •

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

THPME149

Beam Dynamics Issues in the Post Accelerator for the Rare Isotope Ion Beams from ISOL System in RISP

3605

J.G. Hwang, S.W. Jang, E.-S. Kim
Kyungpook National University, Daegu, Republic of Korea
B.H. Choi, D. Jeon, H.J. Kim, H.J. Kim, I. Shin
IBS, Daejeon, Republic of Korea
L. Lee
KNU, Deagu, Republic of Korea

The accelerator for RISP, which is the superconducting technology based heavy ion linear accelerator construction project, is composed mainly of the driver linac for stable ion beam from an ECR ion source and post linac for unstable ion from an ISOL system. The post accelerator can accelerate the unstable ion beams up to 16.5 MeV/u for 132Sn and 16.0 MeV/u for 58Ni, which has the ratio of mass to charge, A/q, of 8.3. The unstable ion beam such as 132Sn from an ISOL system has the large transverse and longitudinal emittances. Hence acceptance and envelope of the post accelerator should optimize for stable operation. The beam was transported by the post-to-driver transport (P2DT) line which consists of a charge stripper, two charge selection sections and a telescope section with the bunching cavities. In this presentation, we will show the criteria for the design of the post accelerator and result of beam tracking simulation from the low energy transport line to the end of post linac. The initial coordinates of the particles were acquired by the tracking simulation from the low energy beam transport (LEBT) line to the medium energy beam transport (MEBT) line.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME149

Export •

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