Peak current reduction in presence of RF phase modulation in the dual RF system

Jiang Bocheng; Zhang Yao; Tsai Cheng-Ying

doi:10.11884/HPLPB202638.250136

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Jiang Bocheng, Zhang Yao, Tsai Cheng-Ying. Peak current reduction in presence of RF phase modulation in the dual RF system[J]. High Power Laser and Particle Beams. doi: 10.11884/HPLPB202638.250136

Citation:

Jiang Bocheng, Zhang Yao, Tsai Cheng-Ying. Peak current reduction in presence of RF phase modulation in the dual RF system[J]. High Power Laser and Particle Beams. doi: 10.11884/HPLPB202638.250136

Jiang Bocheng, Zhang Yao, Tsai Cheng-Ying. Peak current reduction in presence of RF phase modulation in the dual RF system[J]. High Power Laser and Particle Beams. doi: 10.11884/HPLPB202638.250136

Citation:

Jiang Bocheng, Zhang Yao, Tsai Cheng-Ying. Peak current reduction in presence of RF phase modulation in the dual RF system[J]. High Power Laser and Particle Beams. doi: 10.11884/HPLPB202638.250136

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Peak current reduction in presence of RF phase modulation in the dual RF system

doi: 10.11884/HPLPB202638.250136

1.
Laboratory for Ultrafast Transient Facility, Chongqing University, Chongqing 401331, China
2.
School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074, China

Funds: National Natural Science Foundation of China (12405168); The Fundamental Research Funds for the Central Universities, China (2024CDJXY004)

More Information

Author Bio:
Bocheng Jiang, jiangbocheng@cqu.edu.cn

Cheng-Ying Tsai, jcytsai@hust.edu.cn
Corresponding author: Yao Zhang, zhang_yao@cqu.edu.cn。
Received Date: 2025-05-16
Accepted Date: 2025-10-16
Rev Recd Date: 2025-10-04

Available Online: 2025-12-08

Abstract

Abstract

Background
High harmonic cavities are widely used in electron storage rings to lengthen the bunch, lower the bunch peak current, thereby reducing the IBS effect, enhancing the Touschek lifetime, as well as providing Landau damping, which is particularly important for storage rings operating with ultra-low emittance or at low beam energy.
Purpose
To further increase the bunch length without additional hardware costs, the phase modulation in a dual-RF system is considered.
Methods
In this paper, turn-by-turn simulations incorporating random synchrotron radiation excitation are conducted, and a brief analysis is presented to explain the bunch lengthening mechanism.
Results
Simulation results reveal that the peak current can be further reduced, thereby mitigating IBS effects and enhancing the Touschek lifetime. Although the energy spread increases, which tends to reduce the brightness of higher-harmonic radiation from the undulator, the brightness of the fundamental harmonic can, in fact, be improved.
- dual high-frequency system,
- phase modulation,
- beam bunch stretching,
- intra-beam scattering

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References(27)

References

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