Differential cross section measurements for charge-transfer reaction at 10eV region.

10eV 区域电荷转移反应的微分截面测量。

• 批准号: 06640530
• 负责人: ITOH Yoh
• 金额: $ 1.28万
• 依托单位: Josai University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06640530/
• 关键词: Multi-charged ion; Charge-transfer process; Differential cross section; Low energy collision

A small electron-beam-ion-source (EBIS) was designed and constructed in this project, and is connected to the crossed-beam apparatus to measure differential cross sections for chargetransfer process involving multi-charged ions at the collision energy of 10 eV region.The ion-source consists of an electron-gun, drift-tubes, an ion-extractor and an ion-transporting system. A solenoid-coil which is set outside an ultra-high-vacuum chamber is used to confine the electron-beam. This EBIS could produce, for example, O^+ to O^<5+> ions and Ar^+ to Ar^<9+> ions ; the intensity of the O^<2+> or O^<3+> beam after mass-selection was about 0.1 nA,however, after energy selection and the deceleration down to 10 eV region, only a few percent of thebeam was transported to the interaction region. This beam-intensity is the same order or somewhat higher than that obtained by a recoil-ion-source used often for low-energy multicharged ion -atom collision experiments. Whereas the recoil-ion-source needs an accelerated heavy-ion-beam as a pump-beam, the present set-up is very convenient for a small laboratory for the same kind of measurements. An additional advantages of the present set-up is due to that almost all the ions are known to be in the ground states.As a first trial, I measured the angular distribution of O^+ ions produced in the following process at E_<cm>=10eV : O^<2+> (^3P) +He->O^+ (^2P) +He^+ (^2S) +5.52eV.Though the measured angular distribution shows some structure, the statistics of the signal was not enough to compare with theoretical results because a conventional ion-detector which consists of only apertures and a channel-electron-multiplier. To improve the detection efficiency, it is necessary to use a position-sensitive detector system. Therefore, I have started to design a new detector-system using a micro-channel-plate.

本项目设计并建造了一台小型电子束离子源(EBIS)，它与交叉束装置相连，用于测量碰撞能量为10 eV的多电荷离子电荷传输过程的微分截面。离子源由电子枪、漂移管、离子引取器和离子传输系统组成。设置在超高真空室外的螺线管线圈用于对电子束进行限制。例如，这种EBIS可以产生O^+到O^&lt；5+&gt；离子和Ar^+到Ar^&lt；9+&gt；离子；质量选择后的O^&lt；2+&gt；或O^&lt；3+&gt；束流强度约为0.1nA，但经过能量选择和减速到10 eV区域后，只有很少的束流被传输到相互作用区。这种束流强度与通常用于低能多电荷离子-原子碰撞实验的反冲离子源获得的束流强度相同或略高。反冲离子源需要一个加速的重离子束作为泵浦束，而目前的装置对于小型实验室进行同类测量是非常方便的。作为第一次尝试，我测量了在E&lt；cm&gt；=10 eV：O^&lt；2+&gt；(^3P)+He-&gt；O^+(^2P)+He-&gt；O^+(^2P)+He^+(^2S)+5.52 eV时产生的O^+离子的角分布。虽然测量的角分布具有一定的结构，但由于传统的离子探测器只由孔和沟道电子倍增器组成，所以信号的统计不足以与理论结果相比较。为了提高检测效率，有必要使用位置灵敏探测器系统。因此，我已经开始设计一种使用微通道板的新型探测器系统。

项目成果

Y.Itoh: "The measured angular distribution of O^+ions produced in : O^<2+> +He collisions at E_<cm>=10eV." (to be published).

Y.Itoh：“在 E_<cm>=10eV 处的 O^<2> He 碰撞中产生的 O^ 离子的测量角分布。”

Yoh Itoh: "Angular Distribution of O^+ ions prduced in O^<2+> - He at E_<cm> =10eV" 発表予定.

Yoh Itoh：“O^<2+> - He 中 E_<cm> =10eV 处产生的 O^+ 离子的角分布”即将公布。

Yoh Itoh: "Angular distribution of O^+ ions produced in O^<2+>-He at E_<cm>=10eV" 発表予定.

Yoh Itoh：“E_<cm>=10eV 时 O^<2+>-He 中产生的 O^+ 离子的角分布”即将公布。