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991.
微粗糙度光散射研究:(1)散射角分布全空间测量系统 总被引:1,自引:0,他引:1
本文简述光学表面微粗糙度光散射的基本特性。光散射源测量的基本原理,研制的微分散射分布测量系统与两个实验结果。 相似文献
992.
Doubly-excited states of the isoelectronic sequence of H−, in which both electrons are in high principal quantum numbers, are examined on the basis of alternative pictures of the
correlations between the two electrons. Restricting ourselves to the lowest1
S states with both electrons in principal quantum numbern, we parametrise the electron-electron interaction on the basis of these pictures and compare the resulting simple expressions
with more elaborate numerical calculations. This provides further understanding of the nature of correlations in such states.
1984 JILA Visiting Fellow. 相似文献
993.
994.
M. I. Shahzad I. E. Qureshi U. K. Chaudhary H. A. Khan R. Brandt B. A. Kulakov M. I. Krivopustov V. S. Butsev 《Radiation measurements》1995,25(1-4):277-278
Experiments have been carried out to study the ‘heavy fragments’ emitted at wide angles in the interaction of 3.65 A GeV 16O ions with a thick Cu target, using a stack of CR-39 track detectors. Diametric distribution in a stack registering 16O-beam halo are compared with diameters observed in a stack placed downstream at an angle of 25°. There is a strong indication that the heavy fragments are scattered at large angles. 相似文献
995.
角度调谐的光参量振荡器的详细理论计算和实验研究。给出了非共线匹配角度调谐的理论曲线和实验结果,两者符合得很好。最大可调谐输出6mJ,转换效率23%。 相似文献
996.
A telescope of area 4 m2, consisting of horizontal layers of plastic scintillators, neon flash tubes and absorbers was operated at a depth of 754
hg/cm2 in the Kolar Gold Mines. New values for the vertical intensities of muons have been obtained from observations of the angular
distribution over the slant depths ∼ 750–2300 hg/cm2 and are compared with the existing measurements. From the angular distribution observed, we conclude that muons are produced
wholly through the decay of pions and kaons up to energies of the order of 1 TeV. A value of 0.3±0.2 is estimated for theK/π ratio at production, for muon energies around 500 GeV. A decoherence distribution has been obtained for parallel muon events
up to distances of the order of 10 m. From this we conclude that the averageP
t of the parents of muons of energy ∼ 250 GeV is of the order of 0.3 GeV/c. From an analysis of rock showers, we obtain the
cross section for inelastic interaction of muons of mean energy 100 GeV as (3.8±1.5)×10−30 cm2/nucleon. 相似文献
997.
YANG ShuZheng LI HuiLing JIANG QingQuan & LIU MenQuan Institute of Theoretical Physics China West Normal University Nanchong China 《中国科学G辑(英文版)》2007,50(2):249-260
At the event horizon and the cosmological horizon of the stationary axisymmetric Kerr-Newman black hole in the de Sitter space-time background, the tunneling rate of the charged particles is relevant with Bekenstein-Hawking entropy and the real radiation spectrum is not strictly pure thermal, but consistent with the underlying unitary theory in quantum mechanics. This is a feasible interpretation for the paradox of the black hole information loss. Taking the self-gravitation action, energy conservation, angular momentum conservation and charge conservation into account, the derived radiation spectrum is a correct amendment to the Hawking pure thermal spectrum. 相似文献
998.
研究了采用扭转柱面镜光学系统将厄米-高斯光束变换成为具有轨道角动量的拉盖尔-高斯扭转对称光束. 采用本征模式分解的方法分析了扭转柱面镜光学变换系统实现光束变换的原理.利用光束传输矩阵和二阶矩理论分析计算了光束经过扭转柱面透镜变换过程中的轨道角动量传递过程,证明光束与透镜系统的轨道角动量交换发生在第一个柱面透镜处,光束经过第一个柱面透镜后,具有的轨道角动量保持不变.
关键词:
轨道角动量
光束变换
扭转对称光束
轨道角动量传递 相似文献
999.
Miron Ya. Amusia Arkadiy S. Baltenkov Larissa V. Chernysheva 《Central European Journal of Physics》2008,6(1):14-25
We demonstrate rather interesting manifestations of co-existence of resonance features in characteristics of the photoionization
of 3d-electrons in Xe, Cs and Ba endohedral atoms. It is shown that for all of the considered atoms the reflection by the fullerene
shell of photoelectrons produced by the 3d subshell photoionization affects greatly partial photoionization cross-sections of 3d
5/2 and 3d
3/2 levels and respective angular anisotropy parameters, both dipole and non-dipole adding to all of them additional maximums
and minimums. The results obtained demonstrate distinctive differences between the three atoms. The calculations are performed
treating the 3/2 and 5/2 electrons as electrons of different kinds with their spins “up” and “down”. The effect of the C60 shell is accounted for in the frame of the “orange” skin potential model. It is essential that in the considered photon frequency
region the presented resonance features are not affected by the C60polarization.
相似文献
1000.