Solutions of singular integral equations from gas dynamics and plasma physics

In this paper we give the explicit form of the solutions of the singular integral equations associated with some models of gas dynamics and plasma physics which are extensively investigated in the existing literature. In particular, we deal with equations on infinite and semi-infinite contours, where the data are assumed to be meromorphic functions. In this context we rederive some published results and present some new results which show how our method can be successfully used to obtain the explicit form of the solutions in much more general cases than those found in the literature.     

Relaxation oscillation studies in Nd: YAG laser—Some new results

The study of transient behaviour of a pulse pumped solid state laser system has assumed importance on account of SLM generation by self-seeding with the pre-lase signal. This paper reports on the observations of seed pulses for two different Nd: YAG laser rods, one with anti-reflection coating (AR) on end faces and the other without. The latter displays single longitudinal mode behaviour in each of the relaxation pulse train while the former displays multimode behaviour. Our observations are well explained by the ‘active etalon concept’ introduced earlier.     

Excitonic Rabi oscillations in a quantum dot: local field impact

The influence of local fields on the excitonic Rabi oscillations in an isolated, arbitrary shaped quantum dot (QD) has been theoretically investigated. QD interaction with both a classical electromagnetic field and quantum light has been considered. In the classical light, time harmonic and ultrashort pulse excitations are analyzed. The general formalism has been formulated for quantum light and applied to the case of a Fock qubit. Noticeable modification of the Rabi oscillation dynamics induced by the local fields is predicted to be observable in QDs exposed to both classical and quantum light. In particular, the bifurcation and anharmonism in the Rabi oscillations have been revealed under time harmonic excitation and a dependence of the Rabi oscillation period on the QD depolarization has been obtained.     

二维映射神经元模型中的相干双共振

在具有稳定次阈值振荡特性的二维映射神经元模型中,研究了在没有外界输入信号时噪声对体系动力学的影响.通过数值计算发现了当体系的确定性动力学处于静息状态时,噪声可以诱导出神经元膜电位的随机振荡,而且随着噪声强度的变化,这种振荡的相干性具有两个极大值.另外我们还研究了当体系的确定性动力学处于稳定次阈值振荡及神经脉冲状态时的噪声效应,结果表明噪声对体系动力学的影响与其确定性动力学的分岔特性密切相关.     

D^0D^0 mixing and other recent charm results from BABAR

Studies in which BABAR data have shown evidence for mixing in the neutral charm meson system are presented. A new measurement of the lifetime difference parameter ycp = （1.16±0.22±0.18）% is described. Results are also presented from a systematic study of DK and D＊K invariant mass distributions from a 470 fb^-1 sample of asymmetric e^＋e^- interactions recorded by the BABAR detector at the PEP-Ⅱ storage rings. A new charmed-strange meson has been observed with mass [3044 ± 8stat （-5^＋30 ）syst] MeV/c^2 and width [239± 35stat （-42^＋46）syst]MeV/c^2.     

Numerical study of chaotic oscillations in the electron beam with virtual cathode in the external non-uniform magnetic fields

In this Letter the results of theoretical investigations of the chaotic microwave oscillator based on the electron beam with a virtual cathode are presented. Nonlinear non-stationary processes in these electron systems are studied by means of numerical analysis of 2.5D model. It was discovered that the non-uniform external magnetic field value controls the dynamical regime of oscillations in the virtual cathode oscillator. The processes of the chaotization of output microwave radiation are described and interpreted from the point of view of the formation and interaction of electron structures (bunches) in the electron beams. The numerical results have shown that the investigated electron system with virtual cathode could be considered as a promising controlled source of wideband chaotic oscillations in the microwave range.     

Analysis of neutrino mass, mixing and flavor change

Established results on neutrino mass, mixing and flavor change (as of 2009) are briefly reviewed. Status and prospects of unknown neutrino properties (smallest mixing angle, Dirac/Majorana nature, absolute masses and their hierarchy) are also discussed.     

Surface Order Parameter of 4-n-Heptyl-4′-Cyanobiphenyl

We measured the order parameter near the interface between a liquid crystal and the solid substrate treated by several methods. The interfacial order parameter is different according to the surface treatment, and is larger than the bulk order parameter. Moreover, in the temperature above the clearing point, the interfacial order still has a finite value.