IPAC2012 - List of Authors (Shi, J.)

Paper

Title

Page

A Multi Purpose X Band Accelerating Structure

70

M.M. Dehler, A. Citterio, R. Zennaro
Paul Scherrer Institut, Villigen, Switzerland
G. D'Auria, C. Serpico
ELETTRA, Basovizza, Italy
D. Gudkov, A. Samoshkin
JINR, Dubna, Moscow Region, Russia
S. Lebet, G. Riddone, J. Shi
CERN, Geneva, Switzerland

In a collaboration between CERN, PSI and Sincrotrone Trieste (ST), a series of four multipurpose X-band accelerating structures has been designed and fabricated. The structures have 72 cells with a phase advance of 5 pi/6 and include upstream and downstream wakefield monitors to measure the beam alignment. We give an overview of the electrical and mechanical design and describe the fabrication of the first units. We also present the results of the low level RF tests. Using measurements of the internal cell to cell misalignment, the residual transverse wake and the noise floor of the wake field monitors are computed. Furthermore, we present the first experiences running the structures under high power.

Slides MOOBC03 [15.521 MB]

TUPPR015

Choke-Mode Damped Structure Design for the CLIC Main Linac

1840

H. Zha, H. Chen, W.-H. Huang, C.-X. Tang
TUB, Beijing, People's Republic of China
A. Grudiev, J. Shi, W. Wuensch
CERN, Geneva, Switzerland

Choke-mode damped accelerating structures are being studied as an alternative to the CLIC waveguide damped baseline structure. Choke-mode structures hold the potential for much lower pulsed surface heating and reduced cost since no milling is required. We propose a new choke geometry which has significant suppression of higher order dipoles. By impedance matching and detuning of the first dipole pass-band, the wakefield suppression is comparable to the baseline design with waveguide damping. A fully featured choke mode structure with the same accelerating gradient profile and filling time as the nominal CLIC design has been designed. It has the potential to replace the waveguide damped design without changing any of the machine layout or the beam parameters.

WEPPC021

Development of Superconducting Radio Frequency Cavities at SINAP

2248

J.F. Liu, H.T. Hou, C.W. Lu, C. Luo, Z.Y. Ma, D.Q. Mao, J. Shi, Zh.G. Zhang, S.J. Zhao, X. Zheng
SINAP, Shanghai, People's Republic of China
Z.Q. Feng, Z. Li, J.F. Liu, Y.L. Wei, K. Xu, Y.B. Zhao
Shanghai KEY Laboratory of Cryogenics & Superconducting RF Technology, Shanghai, People's Republic of China
H. Yu
Graduate School of the Chinese Academy of Sciences, Beijing, People's Republic of China

This paper presents the development of superconducting radio frequency cavities at Shanghai Institute of Applied Physics (SINAP) mainly focused on the 500MHz band. Firstly, Two KEKB type 500MHz single cell niobium cavities have been fabricated and one of them has been vertical tested successfully in 2010. The highest accelerating gradient of the fabricated cavity higher than 10MV/m was obtained while the quality factor was better than 4·10⁸ at 4.2K. Secondly, a new type of 500MHz single cell cavity has been designed which adopts the fluted beam pipe for higher order modes propagation and a coaxial type high power input coupler. Thirdly, a 500MHz 5-cell superconducting cavity with large aperture, enlarged beam pipe for HOM propagation and high r/Q value has been optimized which can be a candidate cavity for high current FEL and ERL.

Paper	Title	Page
MOOBC03	A Multi Purpose X Band Accelerating Structure	70
	M.M. Dehler, A. Citterio, R. Zennaro Paul Scherrer Institut, Villigen, Switzerland G. D'Auria, C. Serpico ELETTRA, Basovizza, Italy D. Gudkov, A. Samoshkin JINR, Dubna, Moscow Region, Russia S. Lebet, G. Riddone, J. Shi CERN, Geneva, Switzerland
	In a collaboration between CERN, PSI and Sincrotrone Trieste (ST), a series of four multipurpose X-band accelerating structures has been designed and fabricated. The structures have 72 cells with a phase advance of 5 pi/6 and include upstream and downstream wakefield monitors to measure the beam alignment. We give an overview of the electrical and mechanical design and describe the fabrication of the first units. We also present the results of the low level RF tests. Using measurements of the internal cell to cell misalignment, the residual transverse wake and the noise floor of the wake field monitors are computed. Furthermore, we present the first experiences running the structures under high power.
	Slides MOOBC03 [15.521 MB]

TUPPR015	Choke-Mode Damped Structure Design for the CLIC Main Linac	1840
	H. Zha, H. Chen, W.-H. Huang, C.-X. Tang TUB, Beijing, People's Republic of China A. Grudiev, J. Shi, W. Wuensch CERN, Geneva, Switzerland
	Choke-mode damped accelerating structures are being studied as an alternative to the CLIC waveguide damped baseline structure. Choke-mode structures hold the potential for much lower pulsed surface heating and reduced cost since no milling is required. We propose a new choke geometry which has significant suppression of higher order dipoles. By impedance matching and detuning of the first dipole pass-band, the wakefield suppression is comparable to the baseline design with waveguide damping. A fully featured choke mode structure with the same accelerating gradient profile and filling time as the nominal CLIC design has been designed. It has the potential to replace the waveguide damped design without changing any of the machine layout or the beam parameters.

WEPPC021	Development of Superconducting Radio Frequency Cavities at SINAP	2248
	J.F. Liu, H.T. Hou, C.W. Lu, C. Luo, Z.Y. Ma, D.Q. Mao, J. Shi, Zh.G. Zhang, S.J. Zhao, X. Zheng SINAP, Shanghai, People's Republic of China Z.Q. Feng, Z. Li, J.F. Liu, Y.L. Wei, K. Xu, Y.B. Zhao Shanghai KEY Laboratory of Cryogenics & Superconducting RF Technology, Shanghai, People's Republic of China H. Yu Graduate School of the Chinese Academy of Sciences, Beijing, People's Republic of China
	This paper presents the development of superconducting radio frequency cavities at Shanghai Institute of Applied Physics (SINAP) mainly focused on the 500MHz band. Firstly, Two KEKB type 500MHz single cell niobium cavities have been fabricated and one of them has been vertical tested successfully in 2010. The highest accelerating gradient of the fabricated cavity higher than 10MV/m was obtained while the quality factor was better than 4·10⁸ at 4.2K. Secondly, a new type of 500MHz single cell cavity has been designed which adopts the fluted beam pipe for higher order modes propagation and a coaxial type high power input coupler. Thirdly, a 500MHz 5-cell superconducting cavity with large aperture, enlarged beam pipe for HOM propagation and high r/Q value has been optimized which can be a candidate cavity for high current FEL and ERL.