Gyujin Kim, Bongi Oh, Haeryong Yang, Heung-Sik Kang, In Soo Ko, Changbum Kim, Chul Hoon Kim
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引用次数: 0
Abstract
A beam profile monitor has been developed for precise measurement of the electron beam size at the X-ray free-electron laser (XFEL). Given the XFEL’s high beam energy, accurate alignment of optical transition radiation (OTR) is essential due to the small opening angle. To address this, a newly designed monitor enables prealignment of the optical system before installation. The target holder incorporates a specialized configuration to remove coherent optical transition radiation (COTR) arising from the XFEL’s ultra-short bunch length, following a concept similar to that used at SwissFEL. Furthermore, the holder layout was optimized to minimize the vacuum chamber dimensions while increasing the separation between the mirror and the beam path to eliminate diffraction radiation. Experimental results confirm that COTR was effectively removed, and no diffraction radiation was observed in the beam images.
期刊介绍：
The Journal of the Korean Physical Society (JKPS) covers all fields of physics spanning from statistical physics and condensed matter physics to particle physics. The manuscript to be published in JKPS is required to hold the originality, significance, and recent completeness. The journal is composed of Full paper, Letters, and Brief sections. In addition, featured articles with outstanding results are selected by the Editorial board and introduced in the online version. For emphasis on aspect of international journal, several world-distinguished researchers join the Editorial board. High quality of papers may be express-published when it is recommended or requested.
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