IPAC2014 - List of Authors (Kim, E.-S.)

Paper	Title	Page
THPME147	The High Position Resolution Cavity BPM Developments and Measurement for ILC Final Focus System	3599
	S.W. Jang, J.G. Hwang, E.-S. Kim, L. Lee KNU, Deagu, Republic of Korea P. Bambade, O.R. Blanco-García, F. Bogard, S. Wallon LAL, Orsay, France Y. Honda, T. Okugi, T. Tauchi, N. Terunuma KEK, Ibaraki, Japan
	An ultra high position resolution cavity BPM was developed for the final focus system of ATF2, which is a accelerator test facility for ILC final focus system. The main purpose of ATF2 are achievement of 37 nm beam size and nano-meter beam orbit stability at IP(Interaction Point). For these purposes, a few nano meter beam position resolution was required for this cavity BPM, which is called the IP-BPM. The IP-BPM was fabricated 2 blocks of IP-BPM, the first block consists of two cavities in one block and second block consists of single cavity. IP-BPM can measure beam position in vertical and horizontal independently by using rectangular shape single cavity. Three IP-BPMs were installed at ATF IP region inside IP-chamber, and its position resolution was measured. We will present the detailed results on the beam tests.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME147
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THPME146	Bunch Length Measurement by Using a 2-Cell Superconducting RF Cavity in cERL Injector at KEK	3596
	J.G. Hwang, E.-S. Kim Kyungpook National University, Daegu, Republic of Korea T. Miyajima KEK, Ibaraki, Japan
	The development of future light source and linear colliders require high quality electron beams with short bunch length. The measurement of the bunch length is important technique for future electron machine. In general, the bunch length was measured by using deflecting cavity which has the time dependent transverse electromagnetic field. However, the transverse electric field of 2-cell superconducting RF (SRF) cavity can also provide the correlation between the bunch length and beam size as like the role of the deflecting cavity in bunch length measurement. The deflection strength was calibrated by changing the RF phase and the beam offset because the strength of transverse electric field of RF cavity depends on the phase of RF field and the beam offset in the cavity. We will present new way to measure the bunch length by using 2-cell SRF cavity, which has the acceleration field of 15 MV/m, and the measured result with the bunch length of 3 ps in cERL injector.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME146
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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
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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
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Paper

Title

Page

The High Position Resolution Cavity BPM Developments and Measurement for ILC Final Focus System

3599

S.W. Jang, J.G. Hwang, E.-S. Kim, L. Lee
KNU, Deagu, Republic of Korea
P. Bambade, O.R. Blanco-García, F. Bogard, S. Wallon
LAL, Orsay, France
Y. Honda, T. Okugi, T. Tauchi, N. Terunuma
KEK, Ibaraki, Japan

An ultra high position resolution cavity BPM was developed for the final focus system of ATF2, which is a accelerator test facility for ILC final focus system. The main purpose of ATF2 are achievement of 37 nm beam size and nano-meter beam orbit stability at IP(Interaction Point). For these purposes, a few nano meter beam position resolution was required for this cavity BPM, which is called the IP-BPM. The IP-BPM was fabricated 2 blocks of IP-BPM, the first block consists of two cavities in one block and second block consists of single cavity. IP-BPM can measure beam position in vertical and horizontal independently by using rectangular shape single cavity. Three IP-BPMs were installed at ATF IP region inside IP-chamber, and its position resolution was measured. We will present the detailed results on the beam tests.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME147

Export •

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

THPME146

Bunch Length Measurement by Using a 2-Cell Superconducting RF Cavity in cERL Injector at KEK

3596

J.G. Hwang, E.-S. Kim
Kyungpook National University, Daegu, Republic of Korea
T. Miyajima
KEK, Ibaraki, Japan

The development of future light source and linear colliders require high quality electron beams with short bunch length. The measurement of the bunch length is important technique for future electron machine. In general, the bunch length was measured by using deflecting cavity which has the time dependent transverse electromagnetic field. However, the transverse electric field of 2-cell superconducting RF (SRF) cavity can also provide the correlation between the bunch length and beam size as like the role of the deflecting cavity in bunch length measurement. The deflection strength was calibrated by changing the RF phase and the beam offset because the strength of transverse electric field of RF cavity depends on the phase of RF field and the beam offset in the cavity. We will present new way to measure the bunch length by using 2-cell SRF cavity, which has the acceleration field of 15 MV/m, and the measured result with the bunch length of 3 ps in cERL injector.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME146

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

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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)