Au等离子体M带5f-3d跃迁的电子离子碰撞激发速率系数

电子离子碰撞激发速率系数在超组态碰撞辐射模型中真实模拟非局域热动力学平衡Au激光等离子体M带谱 5f 3d跃迁中各种复杂电荷态离子的电离态特性 (譬如离子的平均电离度 ,相对丰度和能级布居数 )是必不可少的。基于准相对论多组态Hartree Fock方法和扭曲波玻恩交换近似 ,采用自编的扭曲波程序ACDW (9)和Fit(9) ,从头计算了Au等离子体M带 5f 3d电子离子碰撞激发速率系数。结果表明 :在“神光II”实验装置诊断的电子温度约 2keV ,电子密度约 6× 10 2 1cm-3 范围内 ,这些电子离子碰撞激发参数有利于采用超组态碰撞辐射模型模拟Au的激光等离子体M带 5f～ 3d细致谱的平均电离度和电荷态分布。     

Au等离子体M带5f-3d跃迁的电子离子碰撞激发速率系数

电子离子碰撞激发速率系数在超组态碰撞辐射模型中真实模拟非局域热动力学平衡Au激光等离子体M带谱5f-3d跃迁中各种复杂电荷态离子的电离态特性(譬如离子的平均电离度,相对丰度和能级布居数)是必不可少的。基于准相对论多组态Hartree Fock方法和扭曲波玻恩交换近似,采用自编的扭曲波程序ACDW（9）和Fit(9),从头计算了Au等离子体M带5f-3d电子离子碰撞激发速率系数。结果表明：在“神光II”实验装置诊断的电子温度约2keV,电子密度约 6×1021cm-3范围内,这些电子离子碰撞激发参数有利于采用超组态碰撞辐射模型模拟Au的激光等离子体M带5f-3d细致谱的平均电离度和电荷态分布。     

Au激光等离子体M带5f-3d跃迁的光谱参数

用超组态碰撞辐射模型模拟非局域热动力学平衡中Au的M带谱5f-3d跃迁的离子电离态特性，激光等离子体的光谱跃迂参数是必不可少的。利用多组态Dirac-Fock广义扩展平均能级方法，用GRASP^2系统地计算了激光Au等离子体中类铁金离子-类锗金离子的M带谱5f-3d的光谱跃迁波长．跃迁几率和振子强度，计算中考虑了重要的核的有限体积效应、Breit修正和QED修正，所得结果和最近的实验数据及理论计算值进行了比较。此结果可应用于对激光等离子体的模拟和诊断。     

激光产生的等离子体透射谱模拟

 根据细致组态方法,采用不分辨的跃迁矩阵模型(UTA) 在组态平均近似下可以容易地计算由高功率激光产生的局域热动平衡状态下的等离子体的不透明度。 采用量子亏损理论计算在激光产生的中Z和高Z元素的等离子体中的高主量子数组态的UTA参数,可节省了大量的计算时间,采用全相对论处理的方法可以快速地计算任何高Z元素等离子体的不透明度。还可以很方便地确定最重要组态以及细致地分析跃迁矩阵。     

激光产生的等离子体透射谱模拟

根据细致组态方法,采用不分辨的跃迁矩阵模型(UTA) 在组态平均近似下可以容易地计算由高功率激光产生的局域热动平衡状态下的等离子体的不透明度。 采用量子亏损理论计算在激光产生的中Z和高Z元素的等离子体中的高主量子数组态的UTA参数,可节省了大量的计算时间,采用全相对论处理的方法可以快速地计算任何高Z元素等离子体的不透明度。还可以很方便地确定最重要组态以及细致地分析跃迁矩阵。     

M带高能光子对发射谱诊断辐射场温度的影响

在稳态近似下通过求解速率方程分别计算了有无M带高能光子存在下,不同温度密度下Cl等离子体的离化度分布以及发射谱,研究了高能光子对等离子体发射谱的影响。研究发现:腔内混有的少量M带高能光子几乎不影响等离子体中重要的离化度分布,但是会激发或者电离各种离子的内壳层电子,从而对发射谱产生重要的影响。因此有M带高能光子存在时,用发射谱诊断等离子体温度时需要同时考虑温度、密度和M带高能光子对发射谱的影响。     

M带高能光子对发射谱诊断辐射场温度的影响

在稳态近似下通过求解速率方程分别计算了有无M带高能光子存在下,不同温度密度下Cl等离子体的离化度分布以及发射谱,研究了高能光子对等离子体发射谱的影响。研究发现:腔内混有的少量M带高能光子几乎不影响等离子体中重要的离化度分布,但是会激发或者电离各种离子的内壳层电子,从而对发射谱产生重要的影响。因此有M带高能光子存在时,用发射谱诊断等离子体温度时需要同时考虑温度、密度和M带高能光子对发射谱的影响。     

第一性原理研究LuAlO3中掺杂Ce3+的4f-5d跃迁性质

通过对基态4f电子采用杂化密度泛函理论方法、对5d激发态采用限制性布居方法,研究了LuAlO₃:Ce³⁺体系4f-5d跃迁的相关性质．结果表明,伴随着4f到5d的跃迁,Ce³⁺与8个最近邻配位O原子的平均键长缩短了0.05 ?,而且Stokes位移计算值与实验值相当吻合．在优化计算得到的LuAlO₃:Ce³⁺体系4f基态局域构型基础上,采用角重叠模型计算了5d能级的晶场分裂,与实验结果吻合较好.     

UTA模型下金M带谱的理论计算

用不可分辩跃迁阵模型(UTA model)计算了金M带0.43nm~0.62nm范围含有的三十五个跃迁阵的特征参数。利用高斯分布线型,对每个离子谱依据UTA的总强度,对整个M带依据离子权重进行叠加,得到了在总体上与实验相一致的结果。     

UTA模型下金M带谱的理论计算

 用不可分辩跃迁阵模型(UTA model)计算了金M带0.43nm~0.62nm范围含有的三十五个跃迁阵的特征参数。利用高斯分布线型,对每个离子谱依据UTA的总强度,对整个M带依据离子权重进行叠加,得到了在总体上与实验相一致的结果。     

金等离子体的荷态分配数的计算

在非局域热动力学平衡(Non-LTE)下,采用类氢近似,计算得出电子密度分别为6.0×10~(20) cm~(-3)、1.4×10~(21) cm~(-3)、1.0×10~(22) cm~(-3)和1.7×10~(22) cm~(-3)的条件下的三体复合、辐射复合、双电子复合系数随电子温度的变化,得出总的复合系数随电子温度的变化关系;结合相关的电离系数得出相应的离子占有数的比,最后,计算出一定电子密度和温度条件下Au~(48+)～Au~(52+)离子的离子丰度,从而得到金等离子体的荷态分配数与电子温度和电子密度的关系.     

金等离子体中7离子系统(Au47+～Au53+)的电荷态分布及其解析函数关系

根据扩展的相对论多组态Dirac-Fock理论计算得到的Au47 ~Au53 离子的平均离子寿命、能级能量和能级简并度,计算了各离子的电离速率常数、复合速率常数和配分函数,并由此得到了离子间的电离-复合平衡常数.基于这些数据,利用电离复合动力学方法研究了金等离子体内7离子系统在一定电子温度和电子密度下的电荷态分布和平均离化度.并给出了Au47 ~Au53 的离子丰度与电子温度和电子密度的函数关系.     

Time-resolved K-shell x-ray spectra of nanosecond laser-produced titanium tracer in gold plasmas

A study of a nanosecond laser irradiation on the titanium-layer-buried gold planar target is presented. The time-resolved x-ray emission spectra of titanium tracer are measured by a streaked crystal spectrometer. By comparing the simulated spectra obtained by using the FLYCHK code with the measured titanium spectra, the temporal plasma states, i.e., the electron temperatures and densities, are deduced. To evaluate the feasibility of using the method for the characterization of Au plasma states, the deduced plasma states from the measured titanium spectra are compared with the Multi-1D hydrodynamic simulations of laser-produced Au plasmas. By comparing the measured and simulated results, an overall agreement for the electron temperatures is found, whereas there are deviations in the electron densities. The experiment-theory discrepancy may suggest that the plasma state could not be well reproduced by the Multi-1D hydrodynamic simulation, in which the radial gradient is not taken into account. Further investigations on the spectral characterization and hydrodynamic simulations of the plasma states are needed. All the measured and FLYCHK simulated spectra are given in this paper as datasets. The datasets are openly available at http://www.doi.org/10.57760/sciencedb.j00113.00032.     

Ion and X-ray techniques used for study of laser-produced plasmas

This review article describes apparatus for ion and X-ray diagnostics, which were used in experimental studies of laser-produced plasmas performed by the IPPLM's team in collaboration with other researchers at IPPLM and PALS Research Centre in Prague (the Czech Republic). The investigations of expanding laser-produced plasma properties in dependence on laser beam parameters were done by means of ion diagnostics devices: ion collectors (ICs), cylindrical ion energy analyzer (IEA) and the mass spectrograph of the Thomson type. At IPPLM, different types of detectors have been developed for measurement of X-ray emission. Properties of laser-produced beams of ions and X-ray radiation were analysed in the cooperative experiments performed with the use of a high-energy iodine laser PALS at the PALS Research Centre ASCR in the Czech Republic and the low-energy repetitive laser at IPPLM.     

Au激光等离子体0.3~0.4nm范围X射线发射谱模拟

 应用自旋-轨道劈裂不可分辨跃迁组理论对高离化Au元素激光等离子体0.3~0.4nm范围的X射线发射谱进行了分析和解释。采用单温局域热动平衡近似,对实验谱进行理论模拟,并根据不可分辨跃迁组强度比得到等离子体电子温度。     

Spectral and ion emission features of laser-produced Sn and SnO_2 plasmas

We have made a detailed comparison of the atomic and ionic debris, as well as the emission features of Sn and SnO_2 plasmas under identical experimental conditions. Planar slabs of pure metal Sn and ceramic SnO_2 are irradiated with1.06 μm, 8 ns Nd:YAG laser pulses. Fast photography employing an intensified charge coupled device(ICCD), optical emission spectroscopy(OES), and optical time of flight emission spectroscopy are used as diagnostic tools. Our results show that the Sn plasma provides a higher extreme ultraviolet(EUV) conversion efficiency(CE) than the Sn O2 plasma.However, the kinetic energies of Sn ions are relatively low compared with those of SnO_2. OES studies show that the Sn plasma parameters(electron temperature and density) are lower compared to those of the SnO_2 plasma. Furthermore, we also give the effects of the vacuum degree and the laser pulse energy on the plasma parameters.     

Analysis of X-ray spectra emitted from laser-produced plasmas of uranium

In this paper, we used the multiconfiguration Dirac-Fock method to generate theoretical X-ray spectra for Co-, Ni-, Cu-, Zn-, Ga-, Ge-, As-, Se-, Br-, Kr-, and Rb-like uranium ions. Using the distribution of these ions in a laser-produced plasma, for different plasma temperatures, we generate theoretical spectra which are compared to experimental data. Electronic supplementary material  Supplementary Online Material The transition probabilities and energies calculated in this work are available in electronic form at http://www.epj.org     

Relative Distribution of Au48 ～ Au52 in Au Plasma by Ionization Dynamics

The present work proposes a theoretical method called ionization dynamics to derive the ionic charge state distribution. Using relativistic quantum mechanics to calculate the energy level lifetime and average ionic lifetime of each ion, the first-order ionization rate constant can be obtained. Based on these data, from the solution of differential equations for consecutive-irreversible ionization reactions, one will be able to derive the ionic charge state distribution.The calculated average positive charge 49.24 of Au48 ～ Au52 and their relative distribution are in good agreement with the results of Lawrence Livermore National Laboratory.     

Consecutive reversible ionization-recombination reactions and ionic charge state distribution of Au plasma

The ionic charge state distribution is an important diagnostics parameter for laser in-ertia confinement fusion (LICF). It is usually obtained by solving Saha equation or using some other models, such as local thermodynamic equilibrium (LTE), corona equilibrium (CE), collision-radiation (CR) and average atom (AA); however, these methods are rather limited for high-Z element plasma. The theory of entropy fluctuation is also a pos-sible method[1]. Lawrence Livermore National Laboratory (…     

喷气式Z箍缩等离子体发射离子束能谱的研究

使用紧凑型汤姆生离子谱仪对喷气式Z箍缩（Z-pinch）等离子体发射的离子束能谱进行了实 验研究.紧凑型汤姆生离子谱仪由入射窗、偏转电磁场、后置针孔及CR-39探测板组成.等离 子体发射的离子束经前置针孔、谱仪入射窗准直后进入偏转电磁场偏转,由后置针孔射出轰 击探测板形成可分辩的抛物线簇.对抛物线簇进行分析处理,得到了等离子体辐射的离子束 能谱及能谱随箍缩状况的变化趋势. 关键词： Z箍缩等离子体 紧凑型汤姆生谱仪 离子束能谱