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91.
Within the concept of the dinuclear system (DNS), a dynamical model is proposed for describing the formation of superheavy nuclei in complete fusion reactions by incorporating the coupling of the relative motion to the nucleon transfer process. The capture of two heavy colliding nuclei, the formation of the compound nucleus and the de-excitation process are calculated by using an empirical coupled channel model, solving a set of microscopically derived master equations numerically and applying statistical theory, respectively. Fusion-fission reactions and evaporation residue excitation functions of synthesizing superheavy nuclei (SHN) are investigated systematically and compared them with available experimental data. The possible factors that affecting the production cross sections of SHN are discussed in this workshop. 相似文献
92.
The recent development of surface growth studies using X‐ray photon correlation spectroscopy in a grazing‐incidence small‐angle X‐ray scattering (Co‐GISAXS) geometry enables the investigation of dynamical processes during kinetic roughening in greater detail than was previously possible. In order to investigate the Co‐GISAXS behavior expected from existing growth models, calculations and (2+1)‐dimension simulations of linear Kuramoto–Sivashinsky and non‐linear Kardar–Parisi–Zhang surface growth equations are presented which analyze the temporal correlation functions of the height–height structure factor. Calculations of the GISAXS intensity auto‐correlation functions are also performed within the Born/distorted‐wave Born approximation for comparison with the scaling behavior of the height–height structure factor and its correlation functions. 相似文献
93.
94.
A tunable infrared plasmonic polarization filter is proposed and investigated in this paper. The filter is based on the sandwich absorption structure which consists of three layers. The top layer is an array of asymmetrical cross resonator.The middle and bottom layers are dielectric spacer and metal film respectively. By absorbing specific wavelength of the incident light perfectly, the reflection spectrum of the structure shows filter performance. The calculated results show that the absorption wavelength is strongly dependent on the length of branch of the asymmetrical cross resonator which is parallel to the light polarization and independent of the length of the vertical one. Therefore, the asymmetrical cross resonator filter structure opens the way for freely tuning the filtering wavelength for a different light polarization. We can fix a resonant wavelength(absorption wavelength) corresponding to one polarization and change the resonant wavelength for the other polarization by adjusting the corresponding branch length of the asymmetrical cross resonator, or change the two resonant wavelengths of both two polarizations at the same time. 相似文献
95.
为了避开复杂繁琐的摄像机标定过程,提出了一种基于CCD摄像机的电子白板系统参数标定新方法,实现了开机自动标定系统参数的功能。采用Harris角点检测算法成功提取了参考点的像素坐标,并直接运用射影变换交比不变性,推导出白板边框图像像素距离与实际物理距离的映射关系式,进而获得了摄像机的光心坐标。简要分析影响系统标定精度的因素,并设计出减小标定误差的方案,最后搭建实验平台标定系统参数。实验结果表明:该标定方法实现简单,应用方便,且对于单位长度为1 cm的标定块而言,标定误差小于0.04 cm。 相似文献
96.
K.C. Vishnubhatla S. Venugopal Rao R. Sai Santosh Kumar Maurizio Ferrari D. Narayana Rao 《Optics Communications》2009,282(23):4537-4542
Herein we present results on the femtosecond laser direct writing and optical characterization studies of two dimensional gratings in fused silica, GE 124, and Foturan™ glasses. Varieties of structures were achieved with varying input energy and spatial orientation of the samples. Various characterization techniques including fluorescence spectroscopy, micro-Raman spectroscopy, and laser confocal microscopy were employed to analyze the structural and physical modifications at the focal volume resulting in change of refractive index. Diffraction efficiencies of 9–12% were observed from the grating structures. A broad-band emission was observed in the laser-modified region of the Foturan glass. The obtained results are analyzed in the light of recent work in similar glasses and exploring the applications of such structures in the fields of photonics. 相似文献
97.
We show that a new beam–spin asymmetry appears in deep inelastic inclusive lepto-production at low transverse momenta when a hadron in the target fragmentation region is observed in association with another hadron in the current fragmentation region. The beam leptons are longitudinally polarized while the target nucleons are unpolarized. This asymmetry is a leading-twist effect generated by the correlation between the transverse momentum of quarks and the transverse momentum of the hadron emitted by the target. Experimental signatures of this effect are discussed. 相似文献
98.
The inclusive production rate of the ρ±(770) vector meson in hadronic Z decays is measured with the ALEPH detector at the LEP collider. A total of 3.2 million hadronic events are selected from data recorded between 1991 and 1995. Decays of ρ±→π0+π± are reconstructed for xE>0.05 and xp>0.05 where xp=pρ/pbeam and xE=Eρ/Ebeam. The average ρ± multiplicity per hadronic event is evaluated to be N(ρ±)=2.59±0.03±0.15±0.04 where the first error is statistical and the second systematic. The third error is from the uncertainty in the extrapolation to xp=xE=0. The rates and differential cross-section are compared with Monte Carlo model predictions and OPAL measurements. Residual Bose–Einstein correlations are found to be an important component in the analysis. 相似文献
99.
100.
Calculated cross sections for the single ionization of atoms (N, Cu, As, Se, Sn, Sb, Te, I, Pb) by electron impact 下载免费PDF全文
By correcting some primary parameters in the semi-classical
Deutsch--M?rk (DM) formula, this paper calculates the absolute
single electron-impact ionization cross sections of atoms N, Cu, As,
Se, Sn, Sb, Te, I and Pb from threshold to 10000eV. The calculated
cross sections are compared with available experimental data and other theoretical results. An excellent agreement was achieved between the calculated and measured cross sections for
these atoms over a wide range of impact energies. 相似文献