Experimental study on non-linear resonant instabilities in space-charge dominated beams with a linear Paul trap

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K05120
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Quantum beam science
• Research Institution: Hiroshima University
• Principal Investigator: ITO Kiyokazu 広島大学, 先端物質科学研究科, 助教 (70335719)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 荷電粒子ビーム / 非中性プラズマ / 非線形共鳴 / 空間電荷効果 / 線形ポールトラップ

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. Actual beam transport channels contain nonlinear fields generated by sextupole magnets and originated from mechanical errors other than the linear field generated by quadrupole magnets. These nonlinear fields are weak, but they sometimes damage beams seriously. Naturally, nonlinear fields caused by mechanical errors exist in the LPT. However, their strengths and structures are uncontrollable. To overcome this limitation, a new type of LPT have been developed in this study. It is also experimentally verified that the sextupole field and the octupole field can be excited by applying suitable voltages to electrodes.

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物理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ビームが必須であり，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れば，加速器を使わずに安全・安価に加速器ビームの実験的研究が行える．