Differential Cross Section and Polarization of Radiative Recombination

The formulae of photon angular distribution and polarization degree for radiative recombination are presented to include the contribution of multipoles and their correlations. A fully relativistic code is then developed to calculate the photon angular distribution and polarization. The calculated polarization degree and differential cross-sections agree well with that of Scofild＇s results within 10%. The effects of multipoles on polarization and angular distribution are investigated. The polarization and the angular distribution become asymmetric when the multipoles are accounted as the electron energy increases.     

Z箍缩Al等离子体X辐射谱线的分离及电子温度的提取

以"强光一号"Z箍缩装置10174发次光谱诊断实验结果为例,描述了一种对Z箍缩等离子体X辐射光谱分离提纯、诊断的方法.对连续辐射谱和特征辐射线谱进行分离,并从连续辐射谱和特征辐射线谱中提取了等离子体电子温度信息.结果显示:等离子体连续谱主要由等离子体中心的高温区(Te=290.7 eV±1.2 eV)和温度较低的壳层区域(Te=95.3 eV±8.3 eV)两部分叠加而成;特征辐射线谱主要反映了等离子体中心的高温区信息,根据非局域热动平衡模型计算提取的电子温度约为299—313 eV,与连续谱诊断结果基本符合.     

Theoretical Study of the Opacity for Mixture Materials at High Temperatures

Using a detailed configuration accounting model with term structures treated by the umresolved transition array model,we have extensively investigated the opacitiesof mixture materials.For plasmas at the temperature of 250 eV and density of 1 g/cm^3,our calculated Rosseland mean opacities are in good agreement with other theoretical results.A high increase in the Rosseland mean opacity to 2944cm^2/g is achieved for a multi-element mixture compared to the value of 1729cm^2/g for pure gold.Various mixtures at other plasma conditions are also studied.     

薄铝埋点等离子体K线光谱半定量诊断

高温等离子体系统中存在等离子体流体力学运动演化过程、离子的离化分布演化动力学过程、高剥离态离子谱发射过程及发射芬光辐射输运过程等，而且高温等离子体系统通常是非平衡系统，所以定量研究高温等离子体系统的发射X光谱和高温等离子体对X光的吸收是一个非常复杂的问题。为了模拟和解释实验测得的激光等离子体发射光谱，提出了一种薄埋点靶：直径为φ200μm厚度为0．1μm的铝点埋在20μm厚的CH膜底衬中，表面再覆盖0．1μm厚CH膜。     

M1 transition energy and rate in the ground configuration of Ag-like ions with 62 ≤ Z ≤ 94

Systematic calculations and assessments are performed for the magnetic dipole(M1)transition energies and rates between the ²F^o_5/2,7/2 levels in the ground configuration 4d104f along the Ag-like isoelectronic sequence with 62≤Z≤94 based on the second-order many-body perturbation theory implemented in the Flexible Atomic Code.The electron correlations,Breit interaction and quantum electrodynamics effects are taken into account in the present calculations.The accuracy and reliability of our results are evaluated through comprehensive comparisons with available measurements and other theoretical results.For transition energies,our results are in good agreement with the recent experimental data obtained from the electron beam ion traps within 0.18%.The maximum discrepancy between our results and those obtained with the large-scale multiconfiguration Dirac–Hartee–Fock calculations by Grumer et al.[Phys.Rev.A 89062501(2014)]is less than 0.13%along the isoelectronic sequence.Furthermore,the corresponding M1 transition rates are also reported.The present results can be used as the benchmark and useful for spectra simulation and diagnostics of astrophysical and fusion plasmas.     

关于低温辐射平均自由程的一些讨论

使用细致组态／不可分辨跃迁系模型计算了不同的温度、密度下金等离子体的辐射平均自由程，注意到了一个普遍存在的理论现象——低温区鼓包现象，并从光子的分频自由程和权重函数两个方面探讨了该现象形成的物理机制．     

离子组态效应对电子传导不透明度的影响

基于相对论Hartree-Fock-Slater 自洽场原子结构模型, 考虑电子-离子间的弹性散射机制, 用分波法和扩展的Ziman 公式对电子传导不透明度作了计算。考虑到等离子体离子环境的影响, 不仅引进了等离子体的结构因子, 而且更细致地考虑了等离子体内离子类型 (组态) 对电子传导     

Theoretical Calculations of Opacity for Non-Local-Thermodynamic-Equilibrium Plasmas

A method is presented to calculate the spectral-resolved opacity for non-local-thermodynamic-equilibrium plasmas. With the present method, the configuration population is obtained by solving the rate equations within the framework of configuration-averaged approximation in which the cross sections are calculated based on the first-order perturbation theory. The transition properties are calculated by using the unresolved transition array model. As the illustration, the frequency-dependent opacities of AI and Au plasmas are calculated and compared with the simulation results of the super configuration collisional radiative code. General agreements are obtained and there are some discrepancies for opacity of high-Z elements.     

Opacity Calculations for Non—Local Thermodynamic Equilibrium Mixtures

Based on the average atom model,a non-local thermodynamic equilibrium (non-LTE) model is developed to calculate opacity for mixtures.This model could be applied to high-Z problems.The mean ionization degrees of SiO2 of the present calculation are slightly higher compared with another model for mixtures.As an example.the opacity of Au and Nd mixture is calculated.The results show concrete non-LTE effects and the increase in opacity of the mixture is shown clearly.     

Ionization Balance in Non-Local-Thermodynamic-Equilibrium Plasmas

A collisional-radiative model is developed for population calculations of plasmas in non-local thermodynamic equilibrium. The rate equations in detailed configuration accounting are solved to obtain ion populations. The configuration averaged rate coefficients are used in the rate equations. The cross sections are calculated based on the first perturbation theory. Wavefunctions required in cross section calculations are obtained by the Hartree-Fock-Slater self-consistent-field model. This kinetic model is applied to low- and medium-Z as well as high-Zplasmas. The results are compared with those of other theoretical models and experiments. The comparisons show that the present results of the mean charge statetheoretical ones, while for high-Z elements, the presentthe experimental ones.for low- and medium-Z elements agree well with other theoretical ones, while for high-Z elements, the present mean ionization stages are about two stages lower than the experimental ones.