IPAC2012 - List of Authors (Kim, H.-G.)

Paper	Title	Page
WEPPC023	Status and Progress of RF System for the PLS-II Storage Ring	2254
	M.-H. Chun, J.Y. Huang, Y.D. Joo, H.-S. Kang, H.-G. Kim, C.D. Park, H.J. Park, I.S. Park, Y.U. Sohn, I.H. Yu PAL, Pohang, Kyungbuk, Republic of Korea
	Funding: Supported by the Korea Ministry of Science and Technology The RF system for the Pohang Light Source (PLS) storage ring was upgraded for PLS-II project of 3.0GeV/400mA from 2.5GeV/200mA. the RF system is commissioning with five normal conducting(NC) RF cavities at total maximum RF power of 280kW to the cavities with two 300kW klystron and two 75kW klystron amplifiers in 2011. The super conducting(SC) cavities will be installed on August 2012 because of long delivery. Therefore three NC RF cavities will be replaced with two SC cavities with cryomodules, and operated with cryogenics, digital low level, and 300kW klystron high power system. Also we are preparing the third SC cavity stand to increase the storage ring current up to 400mA with all insertion devices operation. This paper describes the present installation, commissioning, operation status, upgrade progress, and future plan of the RF system for the upgraded project of PLS-II storage ring.

WEPPC024	Preliminary Test of Superconducting RF Cavities for PLS-II	2257
	Y.U. Sohn, M.-H. Chun, J.Y. Huang, Y.D. Joo, H.-S. Kang, H.-G. Kim, S.H. Nam, C.D. Park, H.J. Park, I.S. Park, I.H. Yu PAL, Pohang, Kyungbuk, Republic of Korea
	Funding: This project is supported by the Korea Ministry of Science and Technology. The main part of the Installation for the PLS-II upgrade was finished in June and is on the way to user operation through elaborate commissioning. Up to now, the achievement is 150 mA beam current at 3 GeV with multi-bunch mode with 5 normal conducting cavities which served in the PLS before. After installation of 2 SRF cavities in the summer of 2012, the PLS-II will have 300 mA beam current with 20 IDs by 2 superconducting RF cavities until July, 2014. Finally, one more superconducting cavity will be added in August, 2014, and beam current will rise to 400 mA. The two SRF cavities are under test and conditioning. The two main subsystems, SRF cavities and ceramic windows were tested independently to confirm their performance. Each cavity recorded its accelerating voltage as 3.27 MV and 3.24 MV at 4.2K, respectively. Two RF windows also passed their specification, 300 kW CW traveling wave and 150 kW CW standing wave. The preliminary tests of SRF cryomodules are reported in the presentation.

THPPC016	PLSII Linac RF Conditioning Status	3311
	H.-S. Lee, J.Y. Huang, W.H. Hwang, H.-G. Kim, K.R. Kim, S.H. Kim, S.H. Kim, S.H. Nam, W. Namkung, S.S. Park, S.J. Park, Y.J. Park, S. Shin PAL, Pohang, Kyungbuk, Republic of Korea
	PLS linac has been upgraded in energy from 2.5 to 3.0 GeV. A klystron supplies RF power of 80 MW four acceleration structures through a SLED. But our machine is not enough RF power to get 3 GeV beam energy. So we have changed the RF scheme in four modules as a klystron supplies RF power of 80 MW two accelerating structures through a SLED. There were several problems during the RF conditioning and beam operation. So we will describe the conditioning results and the current status in this paper.

THPPC057	S-band High Power RF System for 10 GeV PAL-XFEL	3419
	W.H. Hwang, J.Y. Huang, Y.D. Joo, H.-S. Kang, H.-G. Kim, S.H. Kim, H.-S. Lee, Y.J. Park PAL, Pohang, Kyungbuk, Republic of Korea
	In PAL, We are constructing a 10GeV PxFEL project. The output power of the klystron is 80 MW at the pulse width of 4 ㎲ and the repetition rate of 120 Hz. In high power operation, it is important to decrease the rf electric field to protect rf break-down in high power rf components. To obtain the maximum beam, we must reduce the phase difference between waveguide branches including accelerating structure and minimize the environment influences. This paper describes the waveguide system and high power rf components for the PxFEL.

Paper

Title

Page

Status and Progress of RF System for the PLS-II Storage Ring

2254

M.-H. Chun, J.Y. Huang, Y.D. Joo, H.-S. Kang, H.-G. Kim, C.D. Park, H.J. Park, I.S. Park, Y.U. Sohn, I.H. Yu
PAL, Pohang, Kyungbuk, Republic of Korea

Funding: Supported by the Korea Ministry of Science and Technology
The RF system for the Pohang Light Source (PLS) storage ring was upgraded for PLS-II project of 3.0GeV/400mA from 2.5GeV/200mA. the RF system is commissioning with five normal conducting(NC) RF cavities at total maximum RF power of 280kW to the cavities with two 300kW klystron and two 75kW klystron amplifiers in 2011. The super conducting(SC) cavities will be installed on August 2012 because of long delivery. Therefore three NC RF cavities will be replaced with two SC cavities with cryomodules, and operated with cryogenics, digital low level, and 300kW klystron high power system. Also we are preparing the third SC cavity stand to increase the storage ring current up to 400mA with all insertion devices operation. This paper describes the present installation, commissioning, operation status, upgrade progress, and future plan of the RF system for the upgraded project of PLS-II storage ring.

WEPPC024

Preliminary Test of Superconducting RF Cavities for PLS-II

2257

Y.U. Sohn, M.-H. Chun, J.Y. Huang, Y.D. Joo, H.-S. Kang, H.-G. Kim, S.H. Nam, C.D. Park, H.J. Park, I.S. Park, I.H. Yu
PAL, Pohang, Kyungbuk, Republic of Korea

Funding: This project is supported by the Korea Ministry of Science and Technology.
The main part of the Installation for the PLS-II upgrade was finished in June and is on the way to user operation through elaborate commissioning. Up to now, the achievement is 150 mA beam current at 3 GeV with multi-bunch mode with 5 normal conducting cavities which served in the PLS before. After installation of 2 SRF cavities in the summer of 2012, the PLS-II will have 300 mA beam current with 20 IDs by 2 superconducting RF cavities until July, 2014. Finally, one more superconducting cavity will be added in August, 2014, and beam current will rise to 400 mA. The two SRF cavities are under test and conditioning. The two main subsystems, SRF cavities and ceramic windows were tested independently to confirm their performance. Each cavity recorded its accelerating voltage as 3.27 MV and 3.24 MV at 4.2K, respectively. Two RF windows also passed their specification, 300 kW CW traveling wave and 150 kW CW standing wave. The preliminary tests of SRF cryomodules are reported in the presentation.

THPPC016

PLSII Linac RF Conditioning Status

3311

H.-S. Lee, J.Y. Huang, W.H. Hwang, H.-G. Kim, K.R. Kim, S.H. Kim, S.H. Kim, S.H. Nam, W. Namkung, S.S. Park, S.J. Park, Y.J. Park, S. Shin
PAL, Pohang, Kyungbuk, Republic of Korea

PLS linac has been upgraded in energy from 2.5 to 3.0 GeV. A klystron supplies RF power of 80 MW four acceleration structures through a SLED. But our machine is not enough RF power to get 3 GeV beam energy. So we have changed the RF scheme in four modules as a klystron supplies RF power of 80 MW two accelerating structures through a SLED. There were several problems during the RF conditioning and beam operation. So we will describe the conditioning results and the current status in this paper.

THPPC057

S-band High Power RF System for 10 GeV PAL-XFEL

3419

W.H. Hwang, J.Y. Huang, Y.D. Joo, H.-S. Kang, H.-G. Kim, S.H. Kim, H.-S. Lee, Y.J. Park
PAL, Pohang, Kyungbuk, Republic of Korea

In PAL, We are constructing a 10GeV PxFEL project. The output power of the klystron is 80 MW at the pulse width of 4 ㎲ and the repetition rate of 120 Hz. In high power operation, it is important to decrease the rf electric field to protect rf break-down in high power rf components. To obtain the maximum beam, we must reduce the phase difference between waveguide branches including accelerating structure and minimize the environment influences. This paper describes the waveguide system and high power rf components for the PxFEL.