Analytic modeling of instabilities driven by higher-order modes in the HLS Ⅱ RF system with a higher-harmonic cavity

ZHAO Yu-Ning; LI Wei-Min; WU Cong-Feng; WANG Lin

doi:10.1088/1674-1137/37/8/087005

Chinese Physics C> 2013, Vol. 37> Issue(8) : 087005 DOI: 10.1088/1674-1137/37/8/087005

Analytic modeling of instabilities driven by higher-order modes in the HLS Ⅱ RF system with a higher-harmonic cavity

Abstract
HTML
Reference
Related

PDF

Abstract：
The utility of a passive fourth-harmonic cavity plays a key role in suppressing longitudinal beam instabilities in the electron storage ring and lengthens the bunch by a factor of 2.6 for the phase Ⅱ project of the Hefei Light Source (HLS Ⅱ). Meanwhile, instabilities driven by higher-order modes (HOM) may limit the performance of the higher-harmonic cavity. In this paper, the parasitic coupled-bunch instability, which is driven by narrow band parasitic modes, and the microwave instability, which is driven by broadband HOM, are both modeled analytically. The analytic modeling results are in good agreement with those of our previous simulation study and indicate that the passive fourth-harmonic cavity suppresses parasitic coupled-bunch instabilities and microwave instability. The modeling suggests that a fourth-harmonic cavity may be successfully used at the HLS Ⅱ.

References

[1]

Chao A W. Physics of Collective Beam Instabilities in High Energy Accelerators. New York: Wiley, 1993. 117-126[2] Bosch R A, Kleman K J, Bisognano J J et al. Phys. Rev. ST Accel. Beams, 2001, 4: 074401[3] Bosch R A. Phys. Rev. ST Accel. Beams, 2005, 8: 084401[4] WU C F, WANG L, LI W M, ZHAO Y N et al. Preliminary Study of The Higher-Harmonic Cavity for HLS-II. Proceedings of IPAC'10. Kyoto, Japan. 2010[5] Boussard D. CERN Laboratory Report, 1975, No. LabII-rf-Int.-75-2

Access

Get Citation

ZHAO Yu-Ning, LI Wei-Min, WU Cong-Feng and WANG Lin. Analytic modeling of instabilities driven by higher-order modes in the HLS Ⅱ RF system with a higher-harmonic cavity[J]. Chinese Physics C, 2013, 37(8): 087005. doi: 10.1088/1674-1137/37/8/087005

RIS(for EndNote,Reference Manager,ProCite)

BibTex

Txt

Milestone

Received: 2012-10-08
Revised: 1900-01-01

Article Metric

Article Views(3838)
PDF Downloads(174)
Cited by(0)

Policy on re-use

To reuse of subscription content published by CPC, the users need to request permission from CPC, unless the content was published under an Open Access license which automatically permits that type of reuse.

通讯作者: 陈斌, bchen63@163.com

1.
沈阳化工大学材料科学与工程学院沈阳 110142

Analytic modeling of instabilities driven by higher-order modes in the HLS Ⅱ RF system with a higher-harmonic cavity

Corresponding author: WU Cong-Feng,

Received Date: 2012-10-08
Accepted Date: 1900-01-01
Available Online: 2013-08-05

Abstract: The utility of a passive fourth-harmonic cavity plays a key role in suppressing longitudinal beam instabilities in the electron storage ring and lengthens the bunch by a factor of 2.6 for the phase Ⅱ project of the Hefei Light Source (HLS Ⅱ). Meanwhile, instabilities driven by higher-order modes (HOM) may limit the performance of the higher-harmonic cavity. In this paper, the parasitic coupled-bunch instability, which is driven by narrow band parasitic modes, and the microwave instability, which is driven by broadband HOM, are both modeled analytically. The analytic modeling results are in good agreement with those of our previous simulation study and indicate that the passive fourth-harmonic cavity suppresses parasitic coupled-bunch instabilities and microwave instability. The modeling suggests that a fourth-harmonic cavity may be successfully used at the HLS Ⅱ.