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11.
A new solution to modified Bloch equations for a diatomic quantum system consisting of two identical interacting atoms in a field of high-intensity continuous radiation is obtained. On the basis of this solution, the existence of nonlinear sized resonances whose properties strongly depend on the atomic spacing, on the polarization of the external field of radiation, and on the initial inversions of atoms constituting a nanostructural object is shown. Dispersion dependences of induced dipole moments and inversions of atoms of the object are investigated theoretically in the region of sized resonances for various irradiation conditions.  相似文献   
12.
The existence of linear nonstationary optical resonances in a diatomic nanostructural object with a dipole-dipole atomic interaction has been proved. A new solution to the joint system of modified Bloch optical equations and nonlocal field equations is obtained for time intervals much shorter than the times of phase and energy relaxation. Formulas for effective polarizabilities of the object’s atoms, which have a set of dimensional resonances, are derived. The frequencies of these resonances significantly differ from the eigenfrequencies of the object’s atoms, and their properties depend on the interatomic distance, light-pulse duration, initial atomic inversions, and the orientation of the object’s axis relative to the direction of incidence of the external light wave.  相似文献   
13.
We present results of searches for technirho (rho(T)), techniomega (omega(T)), and Z' particles, using the decay channels rho(T),omega(T),Z'-->e(+)e(-). The search is based on 124.8 pb(-1) of data collected by the D0 detector at the Fermilab Tevatron during 1992-1996. In the absence of a signal, we set 95% C.L. upper limits on the cross sections for the processes pp-->rho(T),omega(T),Z'-->e(+)e(-) as a function of the mass of the decaying particle. For certain model parameters, we exclude the existence of degenerate rho(T) and omega(T) states with masses below about 200 GeV. We exclude a Z' with mass below 670 GeV, assuming that it has the same couplings to fermions as the Z boson.  相似文献   
14.
A nonrelativistic model of a hydrogen-like atom is considered. This model is used to calculate corrections to the energy spectrum of the atom. The analysis is based on a Hamiltonian that includes the intratomic fields generated by the electron and the nucleus.  相似文献   
15.
16.
In this paper we study the dispersion relation of thermal non-neutral plasma column by MHD theory. We use the dispersion relation to discuss the stability and dispersive properties in a non-neutral plasma-filled waveguide. The results are in agreement with those of cold non-neutral plasma.  相似文献   
17.
对基于联合变换相关器的像移测量数学原理进行了说明,介绍了面阵CCD的安装位置以及输入图像的获取方法,分析了低信噪比输入图像、相对转动位移对测量精度的影响。应用MATLAB对输入图像进行傅里叶变换得到联合功率谱,对二值化处理的功率谱进行傅里叶变换得到相关输出,用质量中心算法计算出像移量。分析得出,输入图像信噪比大于5dB,测量均方误差小于0.05像素;输入图像相对转动位移在0.1°的范围内,转动位移对测量精度和峰噪比的影响可以忽略不计。综合分析表明像移测量均方误差小于0.05像素。  相似文献   
18.
The stochastic behavior of the strain fields of coupled systems (a fractal layer, a nanotrap, and quantum dots in a fractal multilayer nanosystem) is studied theoretically and numerically. As the semiaxes of a quantum dot shorten, the amplitude of the primary peak falls, a bump emerges on it, and the region of stochastic behavior shrinks in size. As the semiaxes grow, a broadened peak with a stochastic base in the background (a halo-type signal) forms.  相似文献   
19.
Journal of Structural Chemistry - The structure of complex [Pd(acac){P(NEt2)3}2]BF4 (I) is determined by XRD. In the crystal structure of I, the coordination sphere of palladium is characterized by...  相似文献   
20.
Kinetics and Catalysis - The kinetic characteristics of propagating flame were shown to depend on the chemical properties of the contacting solid surface and on the rates of heterogeneous...  相似文献   
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