The three-Coulomb-wave(3C) model is applied to study the single ionization of helium by 2 MeV/amu C6+ impact.Fully differential cross sections(FDCS) are calculated in the scattering plane and the results are compared with experimental data and other theoretical predictions.It is shown that the 3C results of the recoil peak are in very good agreement with experimental observations,and variation of the position of the binary peak with increasing momentum transfer also conforms better to the experimental results.Furthermore,the contributions of different scattering amplitudes are discussed.It turns out that the cross sections are strongly influenced by the interference of these amplitudes.
The effect of multiple rescattering processes on the harmonic emission from He atom in a spatially inhomogeneous field is discussed by solving the one-dimensional time-dependent Schr?dinger equation and the classical equation of motion.By establishing the physical model of the harmonic emission in the inhomogeneous field, we discuss the related characters of the multiple rescatterings process in the harmonic generation process. It shows that the second rescattering rather than the first rescattering tends to determine the harmonic cutoff energy when the inhomogeneous parameter is larger than 0.0055.Additionally, with the classical simulation, the underlying physical mechanism of the continuum–continuum harmonics is also revealed. Moreover, this work may provide new physical insight into the harmonic generation in an inhomogeneous field, and is beneficial to further extract the harmonic emission from molecular systems.
The effect of final-state dynamic correlation is investigated for ionization of atomic hydrogen by 75-keV proton impact by analyzing double differential cross sections.The final state is represented by a continuum correlated wave(CCW-PT)function which accounts for the interaction between the projectile and the target nucleus(PT interaction).The correlated final state is nonseparable solutions of the wave equation combining the dynamics of the electron motion relative to the target and projectile,satisfying the Redmond’s asymptotic conditions corresponding to long range interactions.The transition matrix is evaluated using the CCW-PT function and the undistorted initial state.Both the correlation effects and the PT interaction are analyzed by the present calculations.The convergence of the continuous correlated final state is examined carefully.Our results are compared with the absolute experimental data measured by Laforge et al.[Phys.Rev.Lett.103,053201(2009)]and Schulz et al.[Phys.Rev.A 81,052705(2010)],as well as other theoretical models(especially the results of the latest non perturbation theory).We have shown that the dynamic correlation plays an important role in the ionization of atomic hydrogen by proton impact.While overall agreement between theory and the experimental data is encouraging,detailed agreement is still lacking.However,such an analysis is meaningful because it provides valuable information about the dynamical correlation and PT interaction in the CCW-PT theoretical model.
A dynamically screened three-Coulomb-wave(DS3C) method is applied to study the single ionization of magnesium by electron impact. Triple differential cross sections(TDCS) are calculated in doubly symmetric geometry at incident energies of 13.65, 17.65, 22.65, 27.65, 37.65, 47.65, 57.65, and 67.65 e V. Comparisons are made with experimental data and theoretical predictions from a three-Coulomb-wave function(3C) approach and distorted-wave Born approximation(DWBA). The overall agreement between the predictions of the DS3 C model and the DWBA approach with the experimental data is satisfactory.
考虑核间相互作用,利用修正的库仑玻恩(MCB-PT)模型计算了入射能量为16 Me V的O^(7+)碰撞氦单电离的全微分截面,并将计算结果与最近的实验数据和三体库仑波(3C)模型及连续扭曲波程函初态(CDW-EIS)模型所得结果进行了比较,发现MCB-PT理论结果在中间动量转移条件下binary峰的位置与实验结果符合得很好,且位于动量转移的方向上.此外,分析了扭曲效应对全微分截面的影响,表明随着动量转移的增加,扭曲效应更加明显.
用扭曲波方法,推广了修正的库仑波恩(MCB)近似计算到重离子碰撞He原子电离问题计算.检查了对75 ke V质子碰撞氦原子单电离的全微分截面的应用情况.结果表明,现在的方法定性地产生了实验的峰结构,尤其是在垂直平面.应用MCB方法研究这一碰撞体系中的后碰撞(PCI)效应,发现PCI效应对全微分截面的形状在散射平面和垂直平面都有着强烈的影响.同时,分析了扭曲效应对全微分截面的贡献.表明,随着动量转移的增加,扭曲效应的作用变得越来越重要.尤其是,扭曲效应定性解释了负角区域的结构.
