Development of electromagnets for proof of principle of vertical orbit excursion fixed field accelerator

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K12538
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 80040:Quantum beam science-related
• Research Institution: Kyushu University
• Principal Investigator: Arima Hidehiko 九州大学, 工学研究院, 助教 (20253495)
• Co-Investigator(Kenkyū-buntansha): 森 義治 京都大学, 複合原子力科学研究所, 特任教授 (30124176)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 電磁石開発 / 磁場測定 / 軌道解析 / 垂直軌道推移 / 固定磁場 / 円型加速器

Outline of Final Research Achievements

We aimed to develop a magnet design method for the VFFA focusing system in order to verify the principle of the Vertical orbit excursion Fixed Field Accelerator (VFFA), which is indispensable for the realization of a new type of high-energy, high-intensity circular accelerator. To develop an electron VFFA, which is the world's first VFFA proof-of-principle machine, a multi-coil type magnet composed of multiple coils was adopted. In the focusing system consisting of several cells of magnets, we measured the three-dimensional magnetic field including the leakage field between magnets and established a design method to determine the optimum current distribution to obtain a stable beam orbit. We obtained basic data for magnet design that will lead to future beam transport experiments and other VFFA proof-of-principle experiments.

Free Research Field

加速器工学

Academic Significance and Societal Importance of the Research Achievements

加速に伴いビーム軌道が垂直に移動する円型加速器であるVFFAの原理検証は未だ前例がない。VFFAの原理検証にはビーム進行方向に対し垂直方向に指数関数的に変化していく複雑な磁場分布を有する電磁石を開発する必要があり、そのような電磁石開発例も報告されていない。VFFA電磁石の設計手法の構築や、磁石間の漏れ磁場や水平及び垂直方向の軌道の結合を考慮したビーム軌道解析により得られる成果は、VFFAの原理検証につながる基礎データの取得につながり、VFFA原理検証機開発研究の進展はもちろん、将来の高エネルギー大強度円型加速器実現への寄与のみならずその利用による波及効果も期待できる。