Application of the method of collective coordinates the the quantisation of the two-dimensional higgs model

A comprehensive analysis of the application of the method of collective coordinates to the two dimensional Higgs model is given. First the instanton solution is derived, and the geometry of configuration space, and the construction of Schrodinger wave functionals are discussed. It is then explicitly verified that the Goldstone mode is the projection of the vacuum state onto the generator of the broken symmetry. The elimination of this Goldstone mode by means of the unitary gauge condition is demonstrated to the the crucial point in the construction of a consistent perturbation procedure. The parameter of the broken symmetry group is then used as the collective coordinate for field configurations around a minimum of the interaction. Throughout, the discussion is sufficiently detailed in order to facilitate the application of the method to other fields.     

On the predictability of the positions of the convergence zones in the ocean

The disagreement between the experimental and calculated positions of the first convergence zone are known from many publications. The most probable cause for such a disagreement, namely, the incorrect specification of the input data for the calculations, is considered. The lack of simultaneity between the hydrological surveys of the region and the acoustic experiments is emphasized. The experimental data obtained by the author in five ocean regions are presented. These data characterize the diurnal variability of the distance from the source to the nearest boundary of the convergence zone. The relations proposed by different researchers for calculating the sound speed from the temperature, salinity, and hydrostatic pressure are analyzed. It is shown that these relations lead to a substantial difference in the estimated depth dependence of the hydrostatic gradient of the sound speed. The position of the first convergence zone is calculated for the propagation conditions determined by vertical temperature and salinity profiles with the subsequent recalculation of these profiles into sound speed profiles by using eight different formulas known from the literature. It is shown that different formulas lead to different values of the distance to the first zone; this difference is substantially greater than that between the calculations and experiment. The necessity of improving the recalculation relations in view of the experimental data on sound propagation in natural oceanic waveguides, including the data on the actual positions of the convergence zones, is emphasized.     

建立力学模型,研究单杠运动中旋转的有关问题

建立相关的力学模型,讨论运动员在单杠旋转运动中如何增加旋转能量,杠的刚柔性对旋转运动的影响和伸展、收缩的最佳时机选择等若干问题．充分展示了力学模型对研究问题的重要意义和作用．     

On the Possibility of the Implicit Renormalization of the Casimir Energy

We propose a procedure for renormalizing the Casimir energy that makes the steps that are used in the standard renormalization procedure, that is, regularization, subtraction, and deregularization, implicit. The proposed procedure is based on the calculation of a set of convergent sums, each of which is related to the initial divergent sum of the non-renormalized Casimir energy. Next, we construct a system of linear equations that relates this set of convergent sums to the renormalized Casimir energy. The unknown renormalized Casimir energy is obtained as a result of solving this system of equations. In this case, both the calculations of the convergent sums and the subsequent solution of the system of linear equations are performed with a certain (generally speaking, arbitrary) ordered accuracy; thus, the result is also approximate. The proposed procedure is, first, more computationally effective than the standard one, and, second, applicable not only to the problems where a transcendental equation for the spectrum can be written, but also to the problems where the spectrum is known only numerically.     

On the problem of the distribution of impurity ions in the F-region of the ionosphere

One-dimensional nonisothermal diffusion in ionospheric plasma (the F-region) is considered in the stationary case. The analysis is carried out for two species of positive ions with allowance for the ionization and recombination processes and the effect of gravity. A system of two coupled equations is derived for the concentrations of the electrons and ions. A transition is made to the case when the ions which determine dissociative recombination are impurity ions. For this case criteria are presented whose fulfilment causes the distribution that has been found to coincide with that obtained by Mange [9] without allowance for photochemical processes.     

Design and analysis of the tunnel connecting the beamcorridor and the spectrum hall of the CSNS

There is a tunnel connecting the beamcorridor and the target station in the spectrum hall in the CSNS project.The length of the tunnel is about 20 m.The shielding design of the tunnel is very significant for the persons working in the spectrum hall because the tunnel is not covered ed soil for shielding.In order to reduce the dose rate at the exit of the cable ducts,we use the ISIS construction,which is designed with four turnings,as a reference for the tunnel design.The thickness of the shielding is obtained by a simulationwith the Monte Carlo Code FLUKA.The result is compared with the data obtained with Moyer Mode and the reliability of the simulation is proved.This paper provides the basis for the design of the tunnel.     

Features of the optical absorption of crystals of the fullerene C60 in the region of the orientational phase transition

The absorption coefficient of perfect single crystals of the fullerene C₆₀ is measured in the energy range 1.6–2.1 eV at temperatures from 4.2 to 300 K. An absorption fine structure is discovered in the and is assigned to electronic and vibronic transitions with the production of free excitons and excitons localized on structural defects. It is shown that in the region of the structural phase transition from a face-centered cubic structure to a simple cubic structure the absorption coefficient undergoes a jump, which is associated with an energy shift of the free exciton line toward lower energies. It is discovered that spatial inhomogeneity, which is associated with the growth of the new phase from a finite number of nuclei, appears in the crystal at the time of this transition. Zh. éksp. Teor. Fiz. 114, 2211–2224 (December 1998)     

光电探测器对光谱仪器精度的影响

通过优化光谱探测环节来提高光谱仪器的精度是改进或研制新型光谱仪的重要途径。为此,文章基于对光电成像系统中光学传递函数的研究,建立了光谱图像经探测器积分抽样后重建的数学模型,并在此基础上分析了光电探测器积分抽样特性参数对光谱线频谱的影响,讨论了光谱线半宽度与探测器积分区间宽度、灵敏度及抽样间隔的关系,提出了准确重建光谱线,提高光谱仪器波长精度和光度精度的探测器优化原则。     

海洋环境噪声场对称性分析及噪声消除方法

实际的海洋环境是非常复杂的,存在着海洋自噪声、舰船噪声、生物发声等,阵元接收到的噪声信号存在一定的相关性,此时基于传统阵列信号处理的目标方位估计方法的性能将变差,针对这一问题,提出了一种实部消除方法.首先从阵元接收环境噪声的物理机理出发,将圆环阵接收的噪声场分解为对称噪声场和非对称噪声场,并且研究发现对称噪声场只影响数据协方差矩阵的实部.然后通过消除协方差矩阵实部,达到消除对称噪声场的目的,提高信噪比,但是同时产生了虚假声源.针对虚假声源的问题,提出了基于优化算法重构协方差矩阵实部的方法,消除了虚假声源的影响.仿真分析与海试数据处理结果表明:该方法明显消除了对称噪声,提高了信噪比,改善了阵列信号处理算法的性能.实部消除方法易于实现,有一定的工程应用价值.     

Dependence of the temperature behaviour of the sputtering ratio on the channelled fraction of the ion beam

A method of calculation is presented for the yield of an electron excitation process by a channelled particle in a single encounter with an atomic row or plane in a crystal. It is shown that, if ψ is the initial angle between the ion trajectory and the row or plane, the number of inner-shell electrons excited is an increasing function of ψ whereas the number of outer electrons excited may decrease with increasing ψ.     

Design and analysis of the tunnel connecting the beamcorridor and the spectrum hall of the CSNS

There is a tunnel connecting the beamcorridor and the target station in the spectrum hall in the CSNS project. The length of the tunnel is about 20 m. The shielding design of the tunnel is very significant for the persons working in the spectrum hall because the tunnel is not covered by soil for shielding. In order to reduce the dose rate at the exit of the cable ducts, we use the ISIS construction, which is designed with four turnings, as a reference for the tunnel design. The thickness of the shielding is obtained by a simulation with the Monte Carlo Code FLUKA. The result is compared with the data obtained with Moyer Mode and the reliability of the simulation is proved. This paper provides the basis for the design of the tunnel.     

Effect of the spectral half-width of the driving field on the bistability

The bistability behavior of a nonlinear absorbing medium inside a Fabry–Perot resonator driven by an external quasi-monochromatic field is studied. The driving field is considered to be of a Gaussian and Lorentzian spectral line profile. The effect of the spectral half-width on the bistability is discussed. The mathematical treatment is carried out through an interferometric point of view. The dependence of the driving intensity required to initiate bistability on the standing wave established inside the resonator is represented.     

干涉仪系统传递函数测量及影响因素的分析

波前功率谱密度(PSD)被用于评价惯性约束聚变(ICF)激光驱动器光学元件中频段的波前误差。干涉仪对PSD较高空间频率分量的测量存在失真效应,可通过干涉仪系统传递函数(STF)的检测标定来获得真实的波前PSD分布。采用台阶板位相比较法测得大口径菲索相移干涉仪检测系统在透射和反射检测情形下的传递函数。对传递函数测试算法进行了比较分析,明确了干涉仪系统zoom倍率的改变等因素对传递函数测量的影响,为波前PSD的准确检测奠定了基础。     

Determination of the mass spectrum of the bound state in the framework of the relativistic hamiltonian approach

We propose one a variant of calculation of the energy spectrum of bound state systems with relativistic corrections. In the framework of quantum field theory, an expression that takes into account relativistic corrections to the mass of the bound state with a known nonrelativistic pair interaction potential is proposed on the basis of calculating the asymptotic behavior of correlation functions of the corresponding field currents with the necessary quantum numbers. Excluding the time variables allows one to determine nonperturbative corrections to the interaction potential. The following results have been obtained in the framework of this approach. The nonperturbative corrections arising due to the relativistic nature of a system to the interaction Hamiltonian are determined. The dependence of the constituent mass of bound-state forming particles on the free state mass and on the orbital and radial quantum numbers is analytically derived. The energy level shift of muonic hydrogen taking into account relativistic corrections is calculated. The energy spectrum of a wide class of potentials that describe the Coulomb bound state is analytically derived with relativistic corrections. The mass spectrum of the glueballs and the constituent masses of the gluons are analytically calculated taking into account spin-orbit, spin—spin, and tensor interactions. Our numerical results have shown very good agreement with the lattice data. Taking into account nonperturbative and nonlocality characters of interactions, the mass spectrum of the mesons consisting of light-light and light-heavy quarks with orbital and radial excitations is determined. Our results show that good agreement with the experimental data for the slope and the intercept of the Regge trajectory can be obtained only taking into account the nonperturbative and the nonlocal characters of interactions. The dependences of the constituent masses of constituent particles on the masses of a free state are certain. When quarks are light, then the difference between current and valent masses of quarks is greater than valent masses of quarks, and when quarks are heavy, then the difference between these masses is insignificant. One of the alternative variants of taking nonlocality into account has been suggested for the definition of properties of hadrons at large distances. The dependence of the constituent masses of constituent particles on the radius of confinement is determined.     

关于工件振动对激光扫描在线检测精度影响的研究

根据激光扫描在线检测的特点 ,在理论上对JSY 1型激光扫描尺寸自动检测仪的平均扫描速度和扫描角进行了分析和计算。通过一些实例 ,探讨了工件振动与扫描检测之间的关系。结果表明 :工件振动对激光扫描检测精度的影响很小 ,调整激光扫描完全适用于工件的非接触在线尺寸检测     

用伪色差概念和PW方法设计双折射透镜初始结构

双焦点干涉显微镜因其高稳定性和高分辨率的特点而受到重视,其核心元件双折射透镜由一片双折射晶体和一片光学玻璃胶合而成。为了双折射透镜的设计工作方便,引入“伪色差”概念,定义“伪色散倒数”,从而可以借用现有的初级像差理论,运用PW方法,给出满足不同设计要求的三种双折射晶体和三种玻璃配对的双胶合透镜的初始结构表格,在不同的应用场合,可用OSLO软件进行像差计算和优化设计,取得需要的结果。为了便于评价这种特定的结构,定义紧凑因子7作为一个评价指标。给出采用方解石和ZF1作材料的设计实例,该设计结构紧凑(γ=0．25)。     

Influence of the polarisation of the medium on the radiation of channeled particles

The theory of the electromagnetic radiation from channeled particles is developed with inclusion of a virtual photon interaction with the crystal. Simple estimates are made for the spectral and angular distribution of the radiation. It is shown that the polarisation of the medium may lead to a drastic shrinking of the frequency range allowed for the radiation. The possibility of an increase of the transverse energy of a particle caused by radiation is predicted.     

产生旁瓣的激光波前功率谱密度与焦斑性能分析

 讨论了在放置与不放置焦斑形态控制器件KPP的两种情况下,采用功率谱密度模拟分析有旁瓣焦斑的激光束波前分布的特点,并由此探讨高功率激光驱动器在无旁瓣的聚焦情形下,对入射到打靶透镜的激光束波前畸变量的控制要求。     

产生旁瓣的激光波前功率谱密度与焦斑性能分析

讨论了在放置与不放置焦斑形态控制器件KPP的两种情况下,采用功率谱密度模拟分析有旁瓣焦斑的激光束波前分布的特点,并由此探讨高功率激光驱动器在无旁瓣的聚焦情形下,对入射到打靶透镜的激光束波前畸变量的控制要求。