有组态相互作用理论研究He原子的非谐振光致电离

本文用组态相互作用理论研究Ｈｅ原子的非谐振光致电离。本文详细分析双重激发自电离态，考察第一电离阈值附近的非谐振谱，计算非谐振区的ｅ－Ｈｅ＾＋，＾１＾，＾３Ｐ散射位相移动及来自ｌｓｎｓ＾１＾，＾３Ｓ的光致电离截面。本文计算结果与实验观测值及现有的理论结果相比较，相当符合。     

A1Ⅱ离子3snp^1p1序列能级辐射寿命的非单调变化

本文考虑了一价铝离子双激发干扰态３ｐ４ｓ＾１ｐ１＾０对ｓｎｐ＾１Ｐ１＾０Ｒｙｄｂｅｒｇ序列的强相互作用，多组态ＨＦＲ自洽场方法计算了Ａ１Ⅱ３ｓｎｐ＾１Ｐ１０（ｎ＝３－１０）序列能级的辐射寿命，与已有的实验和理论计算结果进行了比较，结果表明该序列能级寿命随主量子数ｎ呈现非单调变化。     

组态相互作用效应对类钠铜离子自由离速率和分支比的影响

根据组态相互作用理论，研究了组态相互作用对类钠铜离子自电离组态２ｐ＾５３ｓ３ｌ（ｌ＝０，１，２）自电离速率和分支比的影响。结果表明，与单组态近似下的计算相比，组态相互作用显著地改变了上述组态各能级的自由离速率而且使２ｐ＾５３ｓ＾２组态的自电离分支比减少；使２Ｐ＾５３ｓ３ｄ和２ｐ＾５３ｓ３ｄ组态的自电离分支比增加较为明显。     

钡原子6p3/2ns自电离里德伯态的研究

用激光多步激发技术研究了处于６ｐ１／２电离限以下的６ｐ３／２ｎｓ自电离态的光谱。并利用最 Ｒ矩阵的计算结果,结合多通道量子亏损理论进行了理论分析,理论结果与实验光谱相符合。     

类铍离子的电子碰撞电离

用Ｒ－矩阵方法计算了类铍离子Ｎ~（３＋）及Ｏ~（４＋）的电子碰撞电离截面，并讨论了组态１ｓ~２２Ｐｎｌ引起的共振以及一个２ｓ电子被激发到２ｐ轨道同时另一个被电离的截面对总截面的影响，计算结果表明与Ｊａｋｕｂｏｗｉｃｚ的密耦近似结果相一致。     

碱金属基态原子光致电离截面的理论研究

用X_α法和Slater过渡态理论计算了碱金属元素Na、K、Rb、Cs基态原子的光致电离截面;讨论了价电子对原子实的极化对光致电离截面的影响。计算结果同实验值及别的理论值比较表明、用Slater过渡态理论加原子实的极化能够得到比较好的结果.     

固体^3He中的核磁有序和固体^4He中的超流动态

固体＾３Ｈｅ在１ｍＫ附近发生核磁有序，本文介绍了它的磁相图，物理性质和理论模型。固体＾４Ｈｅ中有可能存在像液体＾４Ｈｅ和液体＾３Ｈｅ中出现的超流动态，对理论预言和实验上的探索进行了评述。     

H（1s）原子（e,2e）三重微分散射截面

考虑（ｅ，２ｅ）出射电子动量相关效应及交换影响，对Ｈ（１ｓ）原子靶推出了三重微分散射截面明晰表达式，计算了入射电子能量为１５０ｅＶ，电离电子能量分别为３ｅＶ，５ｅＶ，１０ｅＶ情况下共面及非共面ＴＤＣＳ，结果与实验值符合较好。     

Al^（10＋）的电子碰撞激发和电离

用扭曲波方法计算了Ａｌ￣（１０＋）离子基态和第一激发态的１ｓ、２ｓ和２ｐ电子的激发和电离截面。激发截面与文献［３］的结果符合很好。同时，２ｓ电离截面与文献［４］的结果也是一致的。在电离阈值处实现了激发截面（乘以“态密度”）与电离能量微分截面的光滑联接。     

类钠铜离子的激发自电离

在扭曲波库仑玻恩交换近似下计算了类钠铜离子２ｐ^６３ｓ＋ｅ^-→２ｐ⁵３ｓ３ｌ＋ｅ^-（ｌ＝０，１，２）的内壳层激发截面．结合单组态近似和组态相互作用两种情况下计算的自电离分支比，计算了上述组态的激发自电离截面．结果表明，在入射电子能量为１０９０ｅＶ时，组态相互作用使２ｐ⁵３ｓ３ｄ总的激发自电离截面增大至单组态近似的近两倍；而使２ｐ⁵３ｓ²组态的激发自电离截面减小为单组态近似的３６％；２ｐ⁵３ｓ３ｐ组态的激发自电离截面只是略有下降 关键词：     

Theoretical studies on the photoionization cross-sections of solid silver

An alternative expression for photoionization cross-section of atoms or molecules and a dielectric influence function （DIF） in a high-density system proposed recently are used to study the photoionization cross-sections of solid silver. It is suggested that a density turning point （DTP） of a photoionized system may be viewed as the critical point where the photoionization properties of atoms in a real system may have a notable change. The results show that the present theoretical photoionization cross-sections are in good agreement with the experimental results of a silver crystal both in structure and in magnitude.     

Diagrammatic Representation of Electronic Correlations in Photoionization Process: Application to Scandium

The conversion rules under which an algebraic expression can be obtained from a corresponding photoionization Goldstone diagram have been given systematically in the present work. The electronic correlations in the photoionization processes then could be studied diagrammatically. The application to atomic scandium shows that the present theoretical scheme can give reasonable photoionization cross sections, which agree well with the experimental results.     

Theoretical Studies on Photoionization Cross Sections of Solid Gold

Accurate expression for photoabsorption (photoionization) cross sections of high density system proposed recently is used to study the photoionization of solid gold. The results show that the present theoretical photoionization cross sections have good agreement both in structure and in magnitude with the experimental results of gold crystal. The studies also indicate that both the real part ε' and the imaginary part ε" of the complex dielectric constant ε, and the dielectric influence function of a nonideal system have rich structures in low energy side with a range about 50 eV, and suggest that the influence of particle interactions of surrounding particles with the photoionized particle on the photoionization cross sections can be easily investigated using the dielectric influence function. The electron overlap effects are suggested to be implemented in the future studies to improve the accuracy of theoretical photoionization cross sections of a solid system.     

Photoionization of the excited He atom in Debye plasmas

We present theoretical photoionization cross sections for He 1s2s ¹S and He 1s2p ¹P states in a Debye plasma environment by the complex coordinate rotation method, using a finite L² basis set constructed from one electron Laguerre orbitals. The plasma environment is found to appreciably influence the photoionization cross sections near the ionization threshold. In this regard, the photoionization cross sections of isolated He are compared with other theoretical and experimental results. Our results are in good agreement with the previous results. A new minimum appears in the photoionization cross section curve for the metastable 1s2s ¹S state. Results are given for the S- and D-wave partial photoionization for the excited 1s2p ¹P state.     

Photoionization microscopy

We present the first experimental results of a technique called photoionization microscopy. Photoelectrons ejected in threshold photoionization of Xe are detected in a velocity map imaging apparatus, and interferences between various trajectories by which the electron moves from the atom to the detector are observed. The structure of the interference pattern, which contains the transverse component of the electronic wave function, evolves smoothly with the excess energy above the saddle point. The main observed features are interpreted within the framework of the semiclassical approximation.     

A direct comparison between gas-phase and solid-state Hg 5d photoionization processes

We present an experimental study of the Hg 5d spin-orbit intensity branching ratio in the photon energy range 18–100 eV. The results obtained on cleaved α-HgS exhibit strong differences with respect to the recent gas-phase data by Shannon and Codling. This is the first time that $\text{experimental}$ results on gas-phase photoionization and $\text{experimental}$ results on solid-state photoionization of the same core levels are directly compared to each other. The evidence we provide for solid-state effects in the photoionization process is, therefore, independent of any particular theoretical interpretation of the data.     

The origin and elimination of spurious peaks in threshold electron photoionization spectra

Autoionization electrons in threshold photoionization spectra are known to occur. The effect of such electrons on the interpretation of threshold electron spectra is discussed and a new method is described which enables one to discriminate between zero kinetic energy electrons and energetic electrons in photoionization experiments with little ambiguity. The method largely overcomes the main problem present in some previously described threshold electron studies; namely, the line-of-sight transmission of energetic electrons which gives rise to non-threshold electron peaks. A rejection ratio of 25 is readily obtained for 0.038 eV electrons compared with threshold (zero kinetic energy) electrons and the (small) transition probability for energetic electrons falls off more rapidly than for analysers previously described. Design parameters based on electron trajectory calculations are given for the analyser used, and photoionization results on argon are presented.     

Strong-field photoionization of intense laser fields by controlling optical singularities

The spatial features of a light field, such as in the form of the optical singularities, provide a new degree of freedom for the application of light fields in different areas of science and technology. However, although the exploration of structured light is growing rapidly, the investigation of strong-field photoionization using such light fields is noticeably lagging behind. Here, we present an experimental study that reveals the signatures of intense, structured light fields with controlled optical singularities in strong-field photoionization. The different types of optical singularities can be identified through photoionization observables,i.e., photoelectron momentum distributions(PMDs). By concurrently shifting the locations of the phase and polarization singularities, the focal electric field features can be designated, and subsequently, the photoionization appearances can be manipulated. In this process, the behaviors of the different intense optical singularities are clearly visualized by the PMDs. This work will advance both the strong-field science and singularity optics.     

偶氮苯的同步辐射光电离研究

用同步辐射光电离质谱与符合技术的相结合测定了偶氮苯光电离效率谱，获得了该分子的电离势，导出了分子和分子离子中某些键的解离能以自由基Ｃ６Ｈ５Ｎ２的电离势。测得了不同光子能量激发下的质谱图，并对不同能量时偶氮苯的解离电离方式进行了分析。     

苯的同步辐射光电离效率谱的研究

用合肥国家同步辐射实验室光化学站的实验装置研究了苯分子的光电离质谱，从所得光电离效率谱精确地定出了苯分子的电离势及苯离子的出现热，并首次报道了三个苯离子的离解能。