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71.
The adiabatic hyperspherical approach (AHSA) is applied for the numerical investigation of the scattering processes and resonances in Coulomb three-body mesic atomic systems. The results of the calculations of elastic and inelastic cross sections in low-energy collisions aμ + b (a, b = p, d, t), energies, lifetimes and local characteristics of resonant states of mesic molecular ions n Heaμ+ (n = 3, 4) are presented. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
72.
We consider the problem of option pricing when the underlying asset follows a general semimartingale process. After reviewing the foundations of arbitrage pricing theory for semimartingales and the link with Lévy processes, we introduce a general method to price options in this framework based on Fourier and Wavelet analysis. Received 4 September 2000  相似文献   
73.
核子 (强子 )是夸克、胶子的束缚态 ,由量子色动力学 QCD描述。由于 QCD的基本特性(高能标度下的渐近自由、低能标度下色禁闭及动力学手征对称性破缺 ) ,对核子 (强子 )结构和性质的 QCD图象是标度相关的 .在高能标度下描述强子的是与探测强子结构的硬过程相联系的QCD部分子模型 .强子的夸克、胶子结构信息通过 QCD部分子求和规则得到 .QCD微扰论是适用的理论 .在低能标度时 ,必须发展 QCD非微扰途径来描述核子 (强子 )物理 .这里简要地讨论各种非微扰途径 (格点 QCD、Dyson- Schwinger方程、有效场论、QCD求和规则 )的某些结果和进展 ,并指出 QCD真空结构在描述低能标度下强子物理中担任重要角色 . The nucleon (hadron) is the bound state of guarks and gluons, which is described by the quantum chromodynamics (QCD). Due to the basic properties of QCD (the asymptotic freedom at the high energy scale, the color confinement and the dynamical chiral symmetry breaking at the low energy scale), the QCD picture for the nucleon’s (hadron’s) structure and property is scale dependent. At high energy scale, the QCD parton model, which is relative to the hard process for testing the...  相似文献   
74.
An efficient fast Fourier transform method has been employed to determine correlation function [g(r*)] using the structure factor [S(Q*)] calculated with the rescaled mean spherical approximation (RMSA) and the DLVO potential. Based on this function a parametric (size and charge) study of the ordering in a highly charged and concentrated macroions (an ideal colloid) has been made. The strength of the correlation increases with the increase in the charge on macroions and it saturates after acertain value. Similarly, a critical diameter of the particle depending on the charge on it has been found at which normal feature of the ordering disappears.  相似文献   
75.
The effect of anisotropy caused by a confining potential on the properties of fermionic cold atoms in a triangular optical lattice is systematically investigated by using the dynamical cluster approximation combined with the continuous time quantum Monte–Carlo algorithm.The quantum phase diagrams which reflect the temperature–interaction relation and the competition between the anisotropic parameter and the interaction are presented with full consideration of the anisotropy of the system.Our results show that the system undergoes a transition from Fermi liquid to Mott insulator when the repulsive interaction reaches a critical value.The Kondo effect also can be observed in this system and the pseudogap is suppressed at low temperatures due to the Kondo effect.A feasible experiment protocol to observe these phenomena in an anisotropic triangular optical lattice with cold atoms is proposed,in which the hopping terms are closely related to the lattice confining potential and the atomic interaction can be adjusted via the Feshbach resonance.  相似文献   
76.
The optical absorption coefficients and the changes in the refractive index in GaAs/AlGaAs parabolic quantum dots(QDs) with applied electric and magnetic fields are studied in detail. Analytical expressions for the linear and nonlinear intersubband absorption coefficients and refractive index changes are obtained by using a compact density matrix approach and an iterative procedure. Finally, the calculated results show the incident optical intensity, the frequencies of the confined potential of the QDs and the applied electric and magnetic fields have a great influence on the optical absorption coefficients and refractive index changes in this system.  相似文献   
77.
碳纳米管束中的正电子理论   总被引:1,自引:0,他引:1       下载免费PDF全文
陈祥磊  郗传英  叶邦角  翁惠民 《物理学报》2007,56(11):6695-6700
采用中性原子叠加模型和有限差分方法(SNA-FD)计算了大范围内不同管径的单壁碳纳米管束中的正电子情况,发现对于单壁碳纳米管束,正电子的主要湮没区域,湮没对象和正电子寿命随碳纳米管管径的不同而发生规律性变化.计算得到管径范围在0.8—1.6nm的碳纳米管束的正电子寿命范围为332—470ps,与实验测得的394ps符合较好.  相似文献   
78.
In this work we present a method for determining the optical parameters of turbid media, namely its absorption coefficient (μa) and its reduced scattering coefficient . It is based on the measurement of CW transmittance profiles and analysis of the experimental data by a theoretical model based on the diffusion approximation (DA) of the radiative transfer equation (RTE). The method developed has been investigated with solid polymer probes but it could be applied for liquid materials as well. Experimental results are presented and compared to those of other authors together with a discussion about the accuracy of measurements. In addition, measurements using integrating spheres as well as Monte Carlo simulations are also presented to validate these results.  相似文献   
79.
基于微观sdIBM-2方案和实验单粒子能量值, 在最普遍的哈密顿量下, 用两组不同的核子-核子等效相互作用参数, 分别很好地再现了102Ru核的振动带能谱和转动带能谱及其演化过程. 微观和唯象的研究指认: 1) 这两种激发模式的共存区是能态8+1—12+1(即Ex=2.500—4.000 MeV); 态 8+1关键词: 微观sdIBM-2方案 形状演化 玻色子 102Ru核')" href="#">102Ru核  相似文献   
80.
In this paper, we report structural, morphological, electrical studies of copper iodide (CuI) thin films deposited onto glass substrates by chemical bath deposition (CBD) and successive ionic layer adsorption and reaction (SILAR) methods. CuI thin films were characterized for their structural, morphological and wettability studies by means of X-ray diffraction (XRD), FT-Raman spectroscopy, scanning electron microscopy (SEM), optical absorption, and contact angle measurement methods. Thickness of thin films was 1 ± 0.1 μm measured by gravimetric weight difference method. The CuI thin films were nanocrystalline, with average crystal size of ~60 nm. The FT-IR study confirmed the formation of CuI on the substrate surface. SEM images revealed the compact and cube like structure for CuI thin films deposited by CBD and SILAR methods, respectively. Optical absorption study revealed optical energy gaps as 2.3 and 3.0 eV for CBD and SILAR methods, respectively. Wettability study indicated that CuI thin films deposited by SILAR method are more hydrophobic as compared to CBD method.  相似文献   
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