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arXiv · 1311.1892

Evolutionary genetic optimization of the injector beam dynamics for the ERL test facility at IHEP

Jiao Yi
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Abstract

The energy recovery linac test facility (ERL-TF), a compact ERL-FEL (free electron laser) two-purpose machine, was proposed at the Institute of High Energy Physics, Beijing. As one important component of the ERL-TF, the photo-injector started with a photocathode direct-current gun was designed and preliminarily optimized. In this paper an evolutionary genetic method, non-dominated sorting genetic algorithm II, is applied to optimize the injector beam dynamics, especially in the high-charge operation mode. Study shows that using an incident laser with rms transverse size of 1~1.2 mm, the normalized emittance of the electron beam can be kept below 1 mm.mrad at the end of the injector. This work, together with the previous optimization for the low-charge operation mode by using the iterative scan method, provides guidance and confidence for future constructing and commissioning of the ERL-TF injector.

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Jiao Yi. 2013-11-08. Evolutionary genetic optimization of the injector beam dynamics for the ERL test facility at IHEP. https://doi.org/10.1088/1674-1137%2F38%2F8%2F088102

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