Physics using ultra low-energy pulsed antiprotons

使用超低能量脉冲反质子的物理学

• 批准号: 09044061
• 负责人: HAYANO Ryugo
• 金额: $ 2.5万
• 依托单位: THE UNIVERSITY OF TOKYO
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for international Scientific Research
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09044061/
• 关键词: Antiproton; Antiprotonic Helium Atom; Exotic Atom; Protonium; Laser Spectroscopy; Atomic Collisions; Antihydrogen; CERN; パルスビーム; エキゾチック原子; CPT対称性; 反陽子減速器(AD)

A new pulsed low-energy antiproton source, AD (antiproton decelerator), will start its operation from 1999 at CERN.This research, both experimental and theoretical, was conducted so as to develop research program using the AD beam. At AD, laser spectroscopy of antiprotonic helium atoms, the work we pioneered at the low energy antiproton ring (LEAR), will reach much higher precision. In addtion, study of other exotic systems such as protonium (bound state of an antiproton and a proton) and anti-hydrogen will be conducted. The major results are as follows :1. A proposal of an experiment at CERN AD, called "Atomic Spectroscopy and Collisions using Slow Antiprotons (ASACUSA)" was submitted to CERN, and was approved.2. The design study of-radio frequency quadrupole (RFQ) antiproton decelerator, which can decelerate the 5 MeV beam from the AD to about 50 keV, was completed in collaboration with CERN.3. Detailed analysis of antiprotonic helium laser spectroscopy data was done, and the results were compared with the high-precision results of recent quantum three-body theory. The agreement was better than 2 ppm, from which we could improve the accuracy of antiproton mass from the present value of 50 ppm to 0.5 ppm.4. A conceptual design of an experiment for protonium laser spectroscopy was done. Being a two-body system, it should be possible to deduce antiproton mass from protonium spectroscopy without the help of complicated three-body theories. The proposed scheme will use the low-energy antiprotons from the RFQ, decelerate them further using a catching trap, and form protoniums in vacuum by collision with atomic hydrogens. The estimated accuracy is 10^<-9> or better.

一种新的脉冲低能反质子源，AD（反质子减速机），将于1999年在欧洲核子研究中心开始运行。本文从实验和理论两方面进行了研究，以制定利用AD波束的研究方案。在AD，我们在低能反质子环（LEAR）上率先开展的反质子氦原子激光光谱研究将达到更高的精度。此外，还将对质子（反质子和质子的结合态）和反氢等其他奇异体系进行研究。主要研究结果如下：一项在欧洲核子研究中心进行的名为“原子光谱学和慢反质子碰撞（ASACUSA）”的实验提议被提交给欧洲核子研究中心，并获得批准。与欧洲核子研究中心（CERN.3）合作完成了射频四极子（RFQ）反质子减速器的设计研究，该减速器可以将从AD发射的5 MeV束流减速到50 keV左右。对反质子氦激光光谱数据进行了详细的分析，并与最近量子三体理论的高精度结果进行了比较。该协议优于2 ppm，由此可以将反质子质量的精度从目前的50 ppm提高到0.5 ppm。对质子激光光谱学实验进行了概念设计。作为一个二体系统，不需要复杂的三体理论的帮助，应该可以从质子光谱中推断出反质子的质量。提出的方案将使用来自RFQ的低能反质子，使用捕获阱进一步减速，并通过与氢原子碰撞在真空中形成质子。估计精度为10^<-9>或更好。

项目成果

J.Bosser et al.: "Feasibility study of a decelerating radio frequency quadrupole system for the antiproton decelerator AD." CERN PS/HP Note. 97-36. 1-39 (1997)

J.Bosser 等人：“反质子减速器 AD 减速射频四极系统的可行性研究。”

H.A.Torii, et al.: "Laser Measurements of the density shifts of resonance lines in antiprotonic helium atoms and stringent constraint on the antiproton charge and mass" Physical Review. A59. 223-229 (1999)

H.A.Torii 等人：“反质子氦原子共振线密度位移的激光测量以及对反质子电荷和质量的严格约束”物理评论。

H. A. Torii 他: "Instrumentation for laser-induced annihilations spectroscopy of metastable antiprotonic helium atoms" Nucl. Instr. Meth.A396. 257-271 (1997)

H. A. Torii 等人：“亚稳态反质子氦原子的激光诱导湮没光谱仪”，Nucl.A396（1997）。

G.Ya Korenman: "Effects of collisions on antiprotonic helium" 宇宙研・宇宙空間原子分子過程研究会レポート. (印刷中). (1998)

G.Ya Korenman：“碰撞对反质子氦的影响”ISAS/空间原子和分子过程研究小组的报告（正在出版）。

M.Hori et al.: "Laser spectroscopy studies of state-dependent collisional quenching of the Lifetimes of metastable antiprotonic helium atoms." Physical Review. A58. 1613-1627 (1998)

M.Hori 等人：“亚稳态反质子氦原子寿命的状态相关碰撞猝灭的激光光谱研究。”