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1.
《Current Applied Physics》2015,15(3):319-325
Pd is one of the metals suitable for inducing low-temperature crystallization in Ge. However, it is not clear how residual Pd atoms are integrated into the Ge lattice. Therefore, time-differential γ–γ perturbed angular correlations (TDPAC) technique using the 100Pd(→100Rh) nuclear probe produced by recoil implantation has been applied to study the hyperfine interactions of this probe in single-crystalline undoped Ge. A Pd-vacancy complex aligned along the <111> crystallographic direction with a unique interaction frequency of 8.4(5) Mrad/s has been identified. This complex was measured to have a maximum relative fraction of about 76(4)% following annealing at 350 °C. Further annealing at higher temperatures reduced this fraction, possibly via dissociation of the complex. Calculations suggest dissociation energy of 1.94(5) eV for the complex. DFT calculations performed in this work are in reasonable good agreement with the experimental values for the electric-field gradient of the defect complex in Ge and Si for comparison. The calculations predict a split-vacancy configuration with the Pd on a bond-centred interstitial site having a nearest-neighbour semi-vacancy on both sides (V-PdBI-V) in Ge and Si. 相似文献
2.
The revival of the nondiffracting vortex beam after its interaction with the 2D on axis obstacle is examined. We show that the phase topology and the spatial distribution of the orbital angular momentum of the beam transmitted through the obstacle regenerate to the initial form during further free propagation. We verify that the healing effect appears even if the interaction is accompanied by the exchange of the orbital angular momentum. 相似文献
3.
A sample of 1233 events is used to study the general characteristics of {}^{16}O-Em interactions at 4.5 A GeV/c. Multiplicity and angular distributions of slow particles and correlations among them are discussed. The present data are compared with the corresponding results from the interactions of other projectiles at the same energy and also the same projectile at different energies. The results indicate that black particle production is independent of the energy and mass of the projectile, but for grey particles it is dependent on the mass of projectile. 相似文献
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5.
Two thousand images of resolution 512×512 pixels as a regular matrix pattern of 10×10 elements are stored, where each element is angularly multiplexed 20 times in a 25 μm thickness of dichromated gelatin emulsion without cross-talk effect. The surface area of the matrix is 1 cm2. We show good concordance of the angular selectivity between the experimental result and theory. The diffraction efficiency of each 20 multiplexed images is measured and has nearly the same value. Examples of reconstructed images for multiple applications are given, for example, storage of 160,000 images on a 3′1/2 floppy disc format, which is about 100 min of black and white film. Application can be made to automobile cartography and storage of X-ray images as well as weather forecast images. Colored diffractive images are also possible and are illustrated. 相似文献
6.
采用MSDI严格角动量投影46Ti、48Cr形变HF谱 总被引:1,自引:1,他引:0
采用修正的表面δ相互作用(MSDI),以球形壳模型单粒子态作基矢,对fp壳层区偶偶核46Ti、48Cr进行形变Hartree–Fock(HF)计算,并用形变HF单粒子态构造Slater行列式波函数,即形变HF内禀态,然后对其实施严格角动量投影程序,得到比较合理的结果. 相似文献
7.
为了实验研究粲偶素ψ'级联衰变过程ψ'→γ'xcJ→γ'γJ/ψ,一个用于正确描述全部末态角分布的产生子是必要的.可以通过分析角分布的关联来确定这一过程的多极展开参数(或者等效的螺旋度振幅),而从中可以知道高阶电磁多极矩和相对论修正的贡献,同时可以检验ψ'是不是ψ'(2S)和ψ'(1D)的混合.介绍了一个能完全描述这一过程的角分布的产生子,同时讨论了测量多极参数的测量方法.这些都可以被用在BESⅢ或者CLEOc的分析当中. 相似文献
8.
The decay process J/ψ→p X X→p P,where p,p and P are the proton,antiproton and pseudoscalar states,respectively,has been studied in terms of the angular distribution and the generalized moment analysis methods.The result shows that we can identify the spin,but cannot determine the parity of the baryon resonance state X produced in the process J/ψ→p X X→p P. 相似文献
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10.
The dependence of emission direction of fast electrons on the laser intensity has been investigated. The experimental results show that, at nonrelativistic laser intensities, the emission of fast electrons is mainly in the polarization plane. With the increase of the laser intensity, fast electrons emit towards the laser propagation direction from laser polarization direction. At relativistic laser intensities, fast electrons move away from the laser polarization plane, closely to the reflection direction of the incident laser beam. 相似文献