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The analytic properties theoretical investigations of baryon of scattering amplitudes provide a meeting point for experimental and resonances. Pole positions and residues allow for a parameterization of resonances in a well-defined way which relates different reactions. The recent progress made within the Jiilich model is summarized. 相似文献
105.
The electron acceleration by a finite-amplitude solitary kinetic Alfven wave (SKAW) in the low-β magnetized plasma is presented. It is found that the electron can be ettlciently accelerated in both the parallel and the transverse directions of ambient magnetic field by a finite-amplitude SKAW up to several tenfold Alvin velocity within the time 0.08 μs. These results are greatly different from the case of the electron accelerated by a small- amplitude SKAW. 相似文献
106.
正弦变化的振幅型光瞳滤波器 总被引:6,自引:0,他引:6
光瞳滤波器作为实现超分辨的基本元件之一,它的设计以及制作都非常重要。设计了一种正弦变化的振幅型光瞳滤波器,可以通过调节少量的参量实现各种不同的超分辨模式。选择正弦函数的周期以及光瞳中心点透过率变化两个参量来实现对最终超分辨效果的调节。数值计算结果表明:在整个人射光瞳上的透过率瞳函数分布具有0.5~2个正弦振幅周期时,较为合适。小于0.5个周期将不会有任何超分辨效果,大于2个周期超分辨效果反而变差。数值计算中还注意到,当周期数为整数时,斯特雷尔比将保持0.25不变。对正弦变化振幅型光瞳滤波器的计算结果,显示了其特殊的性质,对实际中制作正弦变化振幅型光瞳滤波器有一定的指导作用。 相似文献
107.
用衍射屏平移相因子计算夫琅禾费衍射场强分布 总被引:3,自引:0,他引:3
用Fresnel-Kirchhoff衍射积分求解夫琅禾费衍射场分布时引入衍射屏平移相因子,可简化对较复杂衍射屏夫琅禾费衍射的讨论,加深对衍射、干涉现象的理解. 相似文献
108.
Using the way of deriving infinitive sum representation of density operator as a solution to the master equation describing the amplitude dissipative channel by virtue of the entangled state representation, we show manifestly how the initial density operator of a single-mode squeezed vacuum state evolves into a definite mixed state which turns out to be a squeezed chaotic state with decreasing-squeezing and deeoherence. We investigate average photon number, photon statistics distributions for this mixed state. 相似文献
109.
High-frequency signals are pervasive in many science and engineering fields.In this work,the effect of high-frequency driving on general nonlinear systems is investigated,and an effective equation for slow motion is derived by extending the inertial approximation for the direct separation of fast and slow motions.Based on this theory,a high-frequency force can induce various phase transitions of a system by changing its amplitude and frequency.Numerical simulations on several nonlinear oscillator systems show a very good agreement with the theoretic results.These findings may shed light on our understanding of the dynamics of nonlinear systems subject to a periodic force. 相似文献
110.
For the first time we derive the dissipating result of an initial two-mode squeezed pure vacuum state passing through a two-mode amplitude dissipative channel described by the direct product of two independent single-mode master equations. Although these two master equations do not mix the two modes (there is no coupling between them), since the two-mode squeezed state is simultaneously an entangled state, the final state which emerges from passing this channel is a two-mode mixed density operator. The compact expression of the outcoming state is obtained, which manifestly shows that as time evolves, the squeezing effect decreases. 相似文献