2025-09-10 高輝度光科学研究センター,理化学研究所
図１ ビーム入射経路の末端に用いられるパルスセプタム磁石の構造。従来の構造（左）と、新しい構造（右）
＜関連情報＞
- http://www.spring8.or.jp/ja/news_publications/press_release/2025/250911/
- https://journals.aps.org/prab/abstract/10.1103/rvbw-ml5n
次世代光源における革新的なオフアクシスビーム入射のための真空内薄型渦電流セプタム磁石 In-vacuum thin eddy-current septum magnet for innovative off-axis beam injection in next-generation light source
Shiro Takano, Kenji Fukami, Takahiro Inagaki, Taiki Iwashita, Chikara Kondo, Mitsuhiro Masaki, Kanichiro Ogata, Masaya Oishi, Yoshiyuki Saito et al.
Physical Review Accelerators and Beams Published: 10 September, 2025
DOI: https://doi.org/10.1103/rvbw-ml5n
Abstract
Beam injection is one of the most crucial issues for next-generation light sources such as diffraction-limited storage rings. We propose a novel transparent off-axis beam injection scheme for low-emittance storage rings of future light sources. The scheme aims to achieve efficient beam injection into a narrow dynamic aperture with small injection amplitude, while minimizing perturbation to the stored beam with transparent beam injection. An in-vacuum thin eddy-current septum magnet is one of the key components of the scheme to achieve the small injection amplitude. A prototype of the magnet with an accommodating ultrahigh vacuum (UHV) chamber was designed and fabricated. Magnet performance of the prototype demonstrated that an injection amplitude as small as 3 mm is feasible, fulfilling the tight constraint of injection amplitude in off-axis beam injection for next-generation light sources. The prototype achieved a UHV pressure of better than 1×10−7 Pa, ensuring the vacuum performance required for stable operation in storage rings.
