Production of cold ion plasma for studying dynamics of high quality beams

2023 Fiscal Year Final Research Report

• Project/Area Number: 21H03737
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 80040:Quantum beam science-related
• Research Institution: Hiroshima University
• Principal Investigator: Ito Kiyokazu 広島大学, 先進理工系科学研究科(先), 助教 (70335719)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 荷電粒子ビーム / イオンプラズマ / 空間電荷効果 / バッファガス冷却

Outline of Final Research Achievements

A charged particle beam traveling in a quadrupole focusing channel is physically almost equivalent to an ion plasma confined in a linear Paul trap (LPT). Its means that we can conduct a systematic experimental study of beam stability with the LPT. The density in the phase-space of an ion plasma in S-PODs is lower than that of beams in advanced linear accelerators. To study dynamics of these space-charge dominated beams, a high phase-space density ion plasma is required. Ion cooling is absolutely essential for creating a high density ion plasma. Buffer-gas cooling is a major method to cool ions confined in ion traps. The achieved ion temperature is roughly equal to temperature of the buffer-gas. It is desirable to use the low temperature buffer-gas to produce a high phase-space density ion plasma. The S-POD system with a buffer gas cooling system have been developed in this study. It is also experimentally verified that the ions are cooled further by cold buffer gas.

Free Research Field

ビーム物理

Academic Significance and Societal Importance of the Research Achievements

荷電粒子を加速したいわゆるビームは基礎科学分野以外にも医療や産業応用などの幅広い分野で利用されており，現代の生活を支える重要な基盤ツールの一つとなっている．様々な分野における次世代技術の開発のためにはより高性能な（=高位相空間密度の）ビームが必要とされている．ビームの高性能化のためには系統的な実験によりその挙動をより深く理解する必要がある．しかし，加速器は非常に高価であり，おいそれと実験することはできない．本課題で製作した実験装置を用いて得られる空間電荷効果が支配的なビームの挙動に関する知見は，次世代・次々世代の高性能加速器設計に関する重要な指針を与える．