2026-09-16 理化学研究所
図1 ビームチョッパーのパルス波形と電子ビームの波形
＜関連情報＞
- https://www.riken.jp/press/2026/20260916_1/index.html
- https://journals.aps.org/prab/abstract/10.1103/3×73-lc4f
熱電子ビームにおけるナノ秒マルチバンチ構造の形成とマルチバンチX線自由電子レーザーパルスの生成 Formation of nanosecond multibunch structure in thermionic electron beams and generation of multibunch x-ray free-electron laser pulses
Kazuaki Togawa, Hirokazu Maesaka, and Vitaliy Goryashko
Physical Review Accelerators and Beams Published: 9 September, 2026
DOI: https://doi.org/10.1103/3×73-lc4f
Abstract
The x-ray free-electron laser (XFEL) facility SACLA uses a thermionic pulsed electron gun and a beam chopper to produce a low-emittance, short-bunch beam. Recently, a new type of fast pulse generator, which utilized wideband rf amplifiers and a new chopper chamber with high-impedance strip-line electrodes, was developed to reliably and accurately cut out a short bunch from the long-pulsed beam emitted from a single-crystal CeB6 hot cathode. Using these apparatuses, we succeeded in forming nanosecond multibunch structure in the thermionic electron beam and generating a double-bunch XFEL pulse with a total pulse energy of 1 mJ at 10 keV. The results will provide new possibilities for XFEL beams: higher intensity, higher coherence, and higher pulse repetition rate.
