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111.
We present some physics possibilities with an iron calorimeter detector (ICAL) and a status report on the feasibility study
to construct such a detector at a future possible India-based Neutrino Observatory (INO). This talk was given at the workshop
on high energy physics phenomenology, WHEPP-8, in Jan. 2004, at IIT Bombay. 相似文献
112.
J. Seke 《Physica A》1997,240(3-4):635-646
The effect of the counter-rotating terms in the Dicke model with cavity losses is examined. Numerical results for the time evolutions of the atomic population inversion, dipole moment, mean-photon number and atomic and field squeezing parameters for an initial coherent field are presented for various numbers of atoms and different cavity dampings. As a consequence of the counter-rotating terms, the appearance of new steady states for atomic population inversion and the mean-photon number is pointed out. 相似文献
113.
114.
Boris F. Samsonov V. V. Shamshutdinova D. M. Gitman 《Czechoslovak Journal of Physics》2005,55(9):1173-1176
We study chains of transformations introduced in B.F. Samsonov and V.V. Shamshutdinova: J. Phys. A: Math. Gen. 38 (2005) 4715, in order to obtain electric fields with a time-dependent frequency for which the equation of motion of a two-level
atom in the presence of these fields can be solved exactly. We show that a polynomial pseudosupersymmetry may be associated
to such chains.
Presented at the 3rd International Workshop “Pseudo-Hermitian Hamiltonians in Quantum Physics”, Istanbul, Turkey, June 20–22,
2005. 相似文献
115.
A mechanism and a model of a ferroin-catalyzed oscillating chemical system are descrined. This reaction presents an excellent example of a far-from-equilibrium system that forms spatial and temporal dissipative structures. The model shows that while the well-stirred system has a unique and stable stationary state, the same reagent spread in a thin layer may form complex spatiotemporal paterns. Stationary periodic patterns of both small and large amplitude, standing waves, and inhomogeneous chaotic oscillations are found in the model. 相似文献
116.
V. I. Bykov T. P. Pushkareva S. I. Fadeev 《Reaction Kinetics and Catalysis Letters》1996,57(1):133-140
The influence of active sites number on the stationary characteristics of kinetic models is analyzed for some nonlinear schemes of conversion on catalyst surface. Mechanisms involving one and two types of active sites are considered. A possibility of critical effects is shown. 相似文献
117.
Direct and inverse problems of oscillations of an anisotropic layer with a cylindrical cavity of an arbitrary cross-sectional
shape under the action of a load applied to the layer surface are considered. An asymptotic approach to solving these problems
with cavities of small relative sizes is proposed. Numerical results of solving direct and inverse problems are presented.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 50, No. 3, pp. 181–189, May–June, 2009. 相似文献
118.
Y. Y. Lau K. R. Chu L. R. Barnett V. L. Granatstein 《International Journal of Infrared and Millimeter Waves》1981,2(3):373-393
The operation of the gyrotron travelling wave amplifier is based on the convective cyclotron maser instability. It is found that this convective instability may become absolute (nonconvective) at a sufficiently high current level, resulting in oscillation instead of amplification. This threshold current for the transition depends sensitively on the applied magnetic field. The axial wavelength and the characteristic frequency of oscillation at the onset of absolute instability are given. It is found that momentum spread has virtually no effect on the threshold current. A small amount of resistive wall loss, however, raises the threshold current significantly. Oscillations due to partial reflection at the ends of the system are also examined. Preliminary experimental results on both types of oscillations are reported and are found to be in good agreement with the theory. 相似文献
119.
Barteld Braaksma 《Journal of Dynamics and Differential Equations》1992,4(3):485-513
We study a system which may serve as a prototype model for excitability. Its long-term behavior is governed by a globally attracting fixed point, but it has the interesting property that an appropriate small perturbation of the equilibrium situation elicits a large (transient) response. Using singular perturbation techniques, the threshold for excitation is determined. Asymptotic expansions for the threshold are given and their validity is proved. An associated system is studied, which yields further quantitative information on the position of the threshold. 相似文献
120.
一年以前 ,人们惊奇地发现 :在相当弱的磁场中 ,并不太强的微波辐照就可以使二维半导体的磁阻产生强烈的振荡 ,振幅的最大值可超过无辐照磁阻值的十几倍 ,最小值可以一直降到零 .全世界众多的凝聚态物理学家争相聚焦到这个领域 ,进行了许多实验和理论研究 ,企图弄清这一意外发现的机理 .经过一年多的努力 ,人们已经掌握了这个现象更多的细节 ,对其物理机制也有了初步了解 .但深入的实验和理论探索可能还要继续相当一段时间 .文章将对这个物理现象及相关的理论模型 ,尤其是目前得到较多赞同的光子辅助磁输运模型 ,作一简单的介绍 . 相似文献