Cr^21＋电子碰撞激发截面和速率系数

在Ｃｏｕｌｏｍｂ－Ｂｏｒｎ交换似和Ｚ标度类氢模型下，计算了“水窗”波段Ｃｒ＾２１＋离子精细结构能级的电子碰撞激发截面和速率系数。计算过程中对有效核电荷的计算作了修改，使其更有效地反映碰撞过程中电子的关联和相对论效应。     

Mn^22＋电子碰撞激发截面和速率系数

采用Ｃｏｕｌｏｍｂ－Ｂｒｏｎ交换近似，在Ｚ标度类氢模型下计处了“水窗”波段Ｍｎ＾２２＋离子精细结构能级的电子碰撞激发截面和速率系数。为了更有效地考虑碰撞过程中电子的关联和相对论效应，在计算中对有效核电荷的计算作了修改。     

一种考虑电磁波驱动效应的等离子碰撞频率分段计算方法

针对高速飞行器等离子鞘套碰撞频率的经验公式忽略电子-带电粒子碰撞以及电磁波对粒子碰撞的驱动效应对碰撞频率计算的影响问题,提出了一种考虑电磁波驱动效应的碰撞频率分段计算方法.该算法以等离子动力论为基础,综合考虑了电子-中性粒子碰撞、电子-带电粒子碰撞以及电磁波驱动效应对碰撞频率计算的影响,定义了一种新参数—–电离热运动比来判断两类碰撞对碰撞频率计算的影响程度,并根据这一参数值的大小分段计算碰撞频率.理论分析和仿真结果表明:所提出的算法在电离热运动比大于5时比经验公式更接近碰撞频率的真实情况,有助于高速飞行器等离子鞘套碰撞频率的计算和诊断以及电波传播特性的计算.     

玻恩近似下电子与离子碰撞的多组态计算

研究电子与离子碰撞激发过程,在波恩近似下,用多组态平面波与多组态库仑波方法计算振子强度与碰撞强度,并且编制了相应程序MCPBA(九)和MCCBX(九)。以四个组态、27个能级的类Ne-锗为例,从基态开始激发。用MCPBA(九)计算了13个包含直接碰撞的过程。用MCCBX(九)给出了全部26个交换效应的碰撞强度。考虑了不同离子波函数对碰撞强度的影响。还与国外扭曲波计算数据进行了比较。结果表明,对某些激发过程必须进行多组态计算,改进离子波函数的计算甚至比改进碰撞电子波函数更为重要。     

类氢离子电子碰撞电离截面的扭曲波计算

在扭曲波库仑玻恩交换似近下用编制的计算程序计算了类氢离子Ｈｅ，Ｃ，Ｎｅ，Ｓｉ，Ｃａ，Ｆｅ的电子碰撞电离截面，并将结果与Ｙｏｕｎｇｅｒ的扭曲波结果作了比较。在２％以内本文的结果与Ｙｏｕｎｇｅｒ的结果一致。并详细研究了半经典交换势对电子碰撞电离截面的效应以及沿等电子数序列变化的规律     

高Z等离子体中的双电子复合与电子碰撞激发

 采用准相对论性Hartree-Fock-Relativistic方法与不可分辨跃迁组模型相结合，对Au和Ta元素的类Ni离子的双电子复合速率，以及Au元素类Cu离子的电子碰撞激发速率进行了计算。计算结果表明，对于Au类Ni离子的3d¹⁰-3d⁹4l5f-3d¹⁰4l双电子复合过程以及类Cu离子的3d¹⁰4l-3d⁹4l5f电子碰撞激发过程，当电子温度高于1.0 keV时，电子离子碰撞激发速率随电子温度增加而增加，双电子复合速率随电子温度增加而减小，并且电子碰撞激发对谱线辐射的贡献要比双电子复合大得多。     

类锌Au~(49+)离子电子碰撞激发速率系数的研究

利用全相对论扭曲波方法和研究电子碰撞激发过程的计算程序REIE06系统计算了类锌Au~(49+)离子从基态(3s~23p~63d~(10)4s~2)的4s、3d、3p和3s电子激发到4 l(l=p、d、f)和5 l(l=s、p、d、f)的碰撞激发强度,研究了在不同入射电子能量下碰撞强度的变化规律,通过对类锌Au~(49+)离子涉及金激光等离子体M带谱,3d→4f和3d→5f电子碰撞激发速率的计算,分析了等离子体中电子温度对碰撞过程的影响.部分计算结果与其它理论及实验结果进行了比较,取得了很好的一致性.     

共面不对称条件下低能电子碰撞电离Ar(3p)的三重微分截面

采用修正的扭曲波玻恩近似方法, 在共面不对称几何条件下, 计算了能量为70.8 eV电子与Ar(3p)碰撞电离的(e, 2e)三重微分截面, 并与最新实验数据进行了比较. 结果表明电子交换效应和后碰撞相互作用在低能电子碰撞的(e, 2e)过程中起着重要作用. 关键词： (e,2e)三重微分截面 扭曲波玻恩近似 后碰撞相互作用 电子交换效应     

电子与原子、离子碰撞过程的相对论效应

在玻恩近似下,建立了高能电子与原子、离于非弹性碰撞过程的相对论性理论计算方法,并以类Li等电子系列为例,阐明了电子与原子、离子非弹性碰撞过程的相对论效应.它包括:1.靶原子的相对论效应,它随原子序数的增加而增大.低z靶(如Li)的相对论效应可以忽略;对Au~(+76)靶的2_3—3p跃迁,广义振子强度相对论性计算值比相应的非相对论性值小27.1%.2.入射电子的相对论效应,它随入射电子能量的增加而增大.对高能入射电子,在特殊角度,要考虑广义振子强度横场项对微分截面的影响.在极端相对论情况下,如入射电子动能 关键词：     

类镍Au~(51+)离子电子碰撞激发特性的研究

利用全相对论扭曲波方法和研究电子碰撞激发过程的计算程序REIE06系统计算了类镍Au~(51+)离子从基态(3s~23p~63d~(10))n=3壳层3 l(l=s、p、d)电子激发到4 l、5 l(l=s、p、d、f)的碰撞激发强度和截面,研究了在不同入射电子能量下截面的变化规律,通过对类镍Au51+离子涉及X射线激光跃迁的相关能级电子碰撞激发速率的计算,分析了等离子体中电子温度对碰撞过程的影响.部分计算结果与其它理论及实验结果进行了比较,取得了很好的一致性.     

Parametric instabilities in quantum plasmas with electron exchange-correlation effects

Parametric instabilities induced by the nonlinear interaction between high frequency quantum Langmuir waves and low frequency quantum ion-acoustic waves in quantum plasmas with the electron exchange-correlation effects are presented.By using the quantum hydrodynamic equations with the electron exchange-correlation correction,we obtain an effective quantum Zaharov model,which is then used to derive the modified dispersion relations and the growth rates of the decay and four-wave instabilities.The influences of the electron exchange-correlation effects and the quantum effects on the existence of quantum Langmuir waves and the parametric instabilities are discussed in detail.It is shown that the electron exchange-correlation effects and quantum effects are strongly coupled.The quantum Langmuir wave can propagate in quantum plasmas only when the electron exchange-correlation effects and the quantum effects satisfy a certain condition.The electron exchange-correlation effects tend to enhance the parametric instabilities,while quantum effects suppress the instabilities.     

相对论小分量波函数对原子光电离截面的影响

利用相对论平均自洽场理论,　研究了相对论波函数的小分量对原子光电离截面的影响。原子核尺寸效应将使波函数小分量对原子光电离截面的影响减弱。由于波函数沿径向空间被压缩,　电子离核的平均半径较小,　波函数小分量对高离化态离子光电离截面的影响比对一般原子要强得多。波函数小分量反映了相对论效应的基本特征,　从而也定性地说明了光电离过程中相对论效应的强弱。The effects of relativistic small radial component on atomic photoionization cross sections have been studied within relativistic average self consistent field theory. Relativistic effects are relatively unimportant for low photon energy, along with a review of high energy photoionization the relativistic effects are quite important. The effects of relativistic small radial component on photoionization process should show breakdown when the nuclear finite size effects is taken into account. The compression of wavefunction into the space near nucleus is so strong in highly charged ions that the electronic radius greatly decreases, and the effects of relativistic small radial component on photoionization cross sections turn to stronger than ordinary atoms. Since relativistic effects are extremely sensitive to the behavior of small radial component, the results are in good agreement with relativistic effects on photoionization cross section.     

荧光光谱法研究蛋白质构象的电磁-温度协同效应

长期以来电磁生物效应受到人们普遍关注，近年来从各个角度进行了相关研究。电磁－温度协同效应是当前的热点。本研究通过电磁场及温度协同对蛋白质影响的研究，发现蛋白质在电磁场作用下的不可逆变性，而且这种变性也遵循Arrhenius规律，并进一步得出电磁－温度协同作用的蛋白质变性模型。本文从分子反应动力学的角度解释了电磁－温度协同效应，并对非热效应作了一定的探讨。     

Competing interaction effects in recording media

In this work we present a study of the effects of easy axis alignment on coupling effects in recording media. We have studied both particulate and thin film media representing both flexible and rigid disc materials. The texture in the systems has been determined via measurements of the angular dependence of remanence and the coupling determined using the well-established ΔM technique. In particulate media only dipolar coupling is present whereas in thin films intergranular exchange effects also occur. In our thin film samples the exchange coupling is weak so that dipolar effects dominate. We find that the dipolar effects in both systems increase with texture, increasing their dominance over exchange effects.     

利用大亚湾中微子实验装置探测超新星中微子

在利用大亚湾中微子实验装置研究超新星中微子探测过程中, 需要考虑到中微子传播过程中受到各种效应的影响, 包括超新星震荡效应、中微子集体效应、 Mikheyev Smirnov Wolfenstein (MSW)效应和地球物质效应等。 由于超新星中微子受到这些效应, 不同味道的中微子之间振荡会发生变化, 因而利用探测某些超新星中微子事例数之比, 就有可能确定中微子的质量层次,得到中微子混合角θ13和中微子绝对质量的信息。 While detecting supernova neutrinos in the Daya Bay neutrino laboratory, several supernova neutrino effects need to be considered, including the supernova shock effects, the neutrino collective effects, the Mikheyev Smirnov Wolfenstein (MSW) effects, and the Earth matter effects. The phenomena of neutrino oscillation is affected by the above effects. Using some ratios of the event numbers of different supernova neutrinos, we propose some possible methods to identify the mass hierarchy and acquire information about the neutrino mixing angle θ13 and neutrino masses.     

Nonlinear Effects in the Cosmic Microwave Background

Major advances in the observation and theory of cosmic microwave background anisotropies have opened up a new era in cosmology. This has encouraged the hope that the fundamental parameters of cosmology will be determined to high accuracy in the near future. However, this optimism should not obscure the ongoing need for theoretical developments that go beyond the highly successful but simplified standard model. Such developments include improvements in observational modelling (e.g. foregrounds, non-Gaussian features), extensions and alternatives to the simplest inflationary paradigm (e.g. non-adiabatic effects, defects), and investigation of nonlinear effects. In addition to well known nonlinear effects such as the Rees–Sciama and Ostriker–Vishniac effects, further nonlinear effects have recently been identified. These include a Rees–Sciama-type tensor effect, time-delay effects of scalar and tensor lensing, nonlinear Thomson scattering effects and a nonlinear shear effect. Some of the nonlinear effects and their potential implications are discussed.     

Beyond the new standard model in neutrino oscillations

We discuss effects of new physics (NP) in neutrino oscillation experiments. Such effects can modify a production neutrino flux, a detection cross-section and a matter transition. As a result, the NP effects change neutrino oscillations both in vacuum and in matter. A relation between the small effects of NP and the oscillation parameters is discussed. It is shown for which parameters the NP effects are suppressed and when they are potentially large. Oscillations of non-unitary mixed neutrinos are presented in more details.     

Giant uniaxial stress-permeability effect on electrical parameters of heterotypic MnZn ferrite devices and electromagnetic effect

The effects of uniaxial stress on permeability and electrical parameters of heterotypic manganite zinc (MnZn) ferrite devices have been investigated. Giant stress-permeability, stress-capacitance and stress-impedance that are independent of skin effects have been simultaneously observed to exist in a wide range of frequency at room temperature. All the uniaxial stress effects enhance with increasing the permeability of the ferrite. The stress-inductance is same as the stress-impedance and reverse to the stress-capacitance in phase. The stress effects under uniaxial pulling force are analogical with those under uniaxial pressing force. A composite of electrostrain/stress-permeability has been fabricated. Its electromagnetic effects have been observed to be homologous with the stress effects and can also exist in wide range of frequency but display some maximums. Analysis shows that both stress and electromagnetic effects originate from the variation of the magnetic domain structure in the ferrites caused by applied mechanical stress.     

Impact of propagation effects on intersubband Rabi flopping in semiconductor quantum wells

We investigate intersubband Rabi flopping in modulation-doped semiconductor quantum wells with and without the propagation effects, respectively. It is shown that propagation effects have a larger impact on Rabi flopping than the nonlinearities rooted from electron-electron interactions in multiple quantum wells. By using ultrashort π pulses, an almost complete population inversion exists if the propagation effects are not considered; while no complete population inversion occurs in the presence of propagation effects. Furthermore, the magnitude of the impact of propagation effects may be controlled by varying the carrier density.     

On second-order optical processes

It is shown that if the full significance of the algebra involved in the performance of time-dependent perturbation calculations is appreciated, it is possible to predict the existence of a range of effects. These include magnetic field-dependent effects which can also be Raman shifted at sum, difference and second harmonic frequencies. The advantages of using these effects in conducting media is pointed out as well as the possible application to surface studies. These effects are all advantageously inproved by using resonance effects and in double-rather than single-beam experiments.