The Charge State of Protons with 90 and 100 keV Energies Decelerated in Hydrogen Plasma

Lei, Yu; Cheng, Rui; Zhao, Yong; Zhou, Xian; Wang, Yu Yu; Chen, Yan Hong; Zhao, Wei; Zhou, Ze Xian; Yang, Jie; Wen, Xin

doi:10.1155/2021/6685626

Cited by 3 publications

(1 citation statement)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…通过谱线激发考虑到等离子体的电子温度可以通过影响能损理论模型中的库仑对数热修正因子 [24] 来改变离子能损数值, 对此进行计算. 对于T 3 实验结果及讨论离子与部分电离等离子体相互作用后的能损分别来源于与自由电子和与束缚电子两部分的贡献 [11] : 1)根据从头计算方法, 考虑该能量下离子束与等离子体相互作用过程中的电离、俘获等截面和物理过程后, 通过求解对应的速率方程, 理论计算了作用过程中的离子电荷态数值, Zhao等 [15] 计算并证实了He 2+ 离子的激发态对实验能损有一定影响; 然而对于质子束而言, Zhang等 [25] 发现激发态对于有效电荷的影响很低; 2) Lei等 [26,27] 利用常用的有效电荷经验公式Kreussler与Gus'kov等模型, 估算了90 -100 keV能区附近的质子在等离子体中的有效电荷态, 得到了类似的结果, 即对于能量为100 keV的质子, 其在等离子体中的有效电荷态可认为是 1 [28] . 根据上述的讨论, 在下文结果分析中, 认为质子束的有效电荷数值维持为1.…”

Section: 部分电离等离子体靶-自由电子密度诊断unclassified

Diagnosis of bound electron density by measuring energy loss of proton beam in partially ionized plasma target

Chen,

Wang,

Zhou

et al. 2024

Acta Phys. Sin.

Self Cite

View full text Add to dashboard Cite

Partially ionized plasma contains the bound electrons aspect which have an impact on the instability of the plasma, among other things. The evolution process of bound electron density cannot be obtained from the popular method applying for diagnosis of the free electron density aspect, in which the existing optical diagnostics fail. In this paper, we introduce a high-precision experiment: the energy loss of a 100 keV proton beam penetrating through the partially ionized hydrogen plasma target was measured based on the platform of ion beam - plasma interaction at the Institute of Modern Physics, Chinese Academy of Sciences. The bound electron density is figured out according to the energy loss model of Bethe theory, the free electron density information obtained by laser interferometry diagnosis and the electron tempercture measureed by spectrum (Te=0.68 eV; nfe =2.41×1017 cm-2). It is found that the bound electron density decreases with the plasma lifetime. The diagnosis of bound electron density by measuring energy loss of ion beam has the advantages of on-line, in-situ and high resolution, and provides a new way to solve the problem of the bound electron density in partially ionized plasma. A COMSOL simulation reveals that the high-temperature free electrons quickly spray out of the plasma area through a mechanical diaphragm, thus the total number of free electrons decreases. In order to maintain a relatively high degree of ionization in this plasma, in principle, more and more bound electrons are ionized to be free electrons, correspondingly the density of bound electrons decreases. The simulation result agrees well with our experimental data. Based on this finding, more detailed plasma target parameter is provied, which is helpful to deepen the understanding of the interaction process between ion beam and plasma. In future, more research work about lowly energy highly charged ions-plasma interaction will be introduced.

show abstract

Section: 部分电离等离子体靶-自由电子密度诊断unclassified

Diagnosis of bound electron density by measuring energy loss of proton beam in partially ionized plasma target

Chen,

Wang,

Zhou

et al. 2024

Acta Phys. Sin.

Self Cite

View full text Add to dashboard Cite

show abstract

In situ ions energy spectrum measurement using a diamond detector in laser-accelerated ions–plasma interaction

Zhou

Guo²,

Cheng

et al. 2022

Nuclear Instruments and Methods in Physics Research Section A:

View full text Add to dashboard Cite

Experimental setup for interaction between highly charged ions and laser-produced plasma near Bohr velocity energy region

Shi,

Cheng,

Wang

et al. 2023

Acta Phys. Sin.

Self Cite

View full text Add to dashboard Cite

Ion energy loss in the interaction between highly charged ions and dense plasmas near the Bohr velocity energy region is one of the important physical problems in the field of high-energy density physics driven by intense heavy ion beams. Based on the 320 kV experimental platform at the Institute of Modern Physics, Chinese Academy of Sciences, an experimental setup is newly built for the research of interaction between ions and laser-produced plasmas near the Bohr velocity, where the ion energy loss and charge state distribution can be experimentally investigated. This paper introduces the new setup in detail, including: the generation and controlling of pulsed ions beam ( ≥ 200 ns); the preparation of high-density laser plasma target (1017 ~ 1021 cm-3); the diagnostics of plasmas and the developed high energy resolution ion measurement system (＜1%). In the experiment, the charge distribution was measured where the Xe15+ ions with 4 MeV penetrated through the laser-produced Al plasma target. The charge-state analysis device observed that the different resutls without and with the plasmas, in which the outgoing Xe ions charge-state changes correspondingly from the 15+ to 10+, thus the electron capture process is believed dominates. In addition, the proton energy loss was measred too by using the magnetic spectrometer, and the experimental energy loss is about 2.0 keV which is significantly higher than those theoretical predictions by a factor of 30%. In our consideration, the possible reason can be deduced to that in the near Bohr velocity energy regime, the first-order Born approximation condition is not valid, thus the Bethe and SSM models fail to represent the experimental results. In future, a systematic study will be performed based on our ions-plasmas ineteraction setups and the energy loss and charge state data will be introduced.

show abstract

The Charge State of Protons with 90 and 100 keV Energies Decelerated in Hydrogen Plasma

Cited by 3 publications

References 45 publications

Diagnosis of bound electron density by measuring energy loss of proton beam in partially ionized plasma target

Diagnosis of bound electron density by measuring energy loss of proton beam in partially ionized plasma target

In situ ions energy spectrum measurement using a diamond detector in laser-accelerated ions–plasma interaction

Experimental setup for interaction between highly charged ions and laser-produced plasma near Bohr velocity energy region

Contact Info

Product

Resources

About