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arXiv · 1406.6427

Analysis of the microbunching instability in a mid-energy electron linac

Dazhang Huang·Qiang Gu·Zhen Wang·Meng Zhang·King Yuen Ng
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Abstract

Microbunching instability usually exists in the linear accelerator (linac) of a free electron laser (FEL) facility. If it is not controlled effectively, the beam quality will be damaged seriously and the machine will not operate properly. In the electron linac of a soft X-Ray FEL device, because the electron energy is not very high, the problem can become even more serious. As a typical example, the microbunching instability in the linac of the proposed Shanghai Soft X-ray Free Electron Laser facility (SXFEL) is investigated in detail by means of both analytical formulae and simulation tools. In the study, a new mechanism of introducing random noise into the beam current profile as the beam passes through a chicane-type bunch compressor is proposed. The higher-order modes that appear in the simulations suggest that further improvement of the current theoretical model of the instability is needed.

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Dazhang Huang, Qiang Gu, Zhen Wang, Meng Zhang, King Yuen Ng. 2014-06-25. Analysis of the microbunching instability in a mid-energy electron linac. https://doi.org/10.1088/1674-1137%2F39%2F3%2F038101

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