Red-violet asymmetry in pearl satellites' birth     

F.Z. Feygin  YU.P. Kurchashov  V.A. Troitskaya  K. Dobeš 《Planetary and Space Science》1985,33(3):271-273

A high resolution numerical sonagram of Pc-1 magnetic record has shown that single narrow lines of Pc-1 spectra produce lower frequency (“red-shifted”) satellite lines more than twice as often as their higher frequency (“violet”) counterparts. The violet satellites usually emerge only when at least two ancestor lines are present simultaneously.  相似文献   

Dissipation Rate of Turbulence in a Water Layer under Wind Waves Based on Data of a Laboratory Experiment     

Polnikov  V. G.  Baidakov  G. A.  Troitskaya  Yu. I. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(5):492-501

Izvestiya, Atmospheric and Oceanic Physics - The aim of this work is to obtain estimates and parameterization of the dissipation rate of the turbulence kinetic energy (TKE dissipation), ε,...  相似文献   

Statistical properties of the atmospheric turbulent boundary layer over steep surface waves     

Yu. I. Troitskaya  D. A. Sergeev  O. S. Ermakova  G. N. Balandina 《Doklady Earth Sciences》2010,433(1):922-926

A new method of digital optical anemometry (Particle Image Velocimetry, PIV) of turbulent flows is suggested and implemented in the laboratory; it is based on the use of continuous laser radiation and high-speed video photography, providing continuous statistical ensembles of flow velocity fields. Application of the method to the study of wind field over waves has allowed us to perform, for the first time, direct measurements of velocity fields, averaged over turbulent pulsations induced by waves in the air flow. The experiments demonstrated that the velocity fields, averaged over the turbulent pulsations, are nonseparated even in the case of steep and breaking waves, when separation of the flow from the wave crests in the instantaneous fields is observed. Based on comparison with the experimental data, it is shown that the average wind fields over waves are described well quantitatively in the framework of semiempirical closure models of turbulence.  相似文献   

Nuclear Aspects of the Solar Neutrino Problem     

H. Oberhummer  A.N. Ivanov  N.I. Troitskaya  M. Faber 《Astrophysics and Space Science》1997,258(1-2):133-144

The present status of the nuclear reaction rates determining the solar neutrino flux is discussed. This includes the reaction rates for the two branching ratios of the three pp-chains involving the reactions 3He(3He,2p)4He and 3He(4He,γ)7Be for the first branching, and 7Be(e−, νe)7Li and 7Be(p, γ)8B for the second branching. Mainly we will concentrate on the basic nuclear reaction p + p → D + e+ + νe of the pp-chains. This reaction rate can only be determined using the theoretical methods. The present status of the application of the relativistic field theory model of the deuteron for this reaction will be discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Negative correlations of variations in near-water wind and surface wind waves     

Yu. I. Troitskaya  I. S. Dolina  A. V. Ermoshkin  V. V. Bakhanov  E. M. Zuikova  I. A. Repina  V. I. Titov 《Izvestiya Atmospheric and Oceanic Physics》2008,44(4):491-506

The relationship between the intensity of surface wind waves and near-water wind is analyzed. The data of measuring wind waves and near-water wind under natural conditions in the Black Sea (July 2004) and Norwegian Sea (June 2003, 16th cruise of the R/V Akademik Sergei Vavilov) are used. A phenomenon of negative correlations has been found between the intensity of wind waves and near-water wind in regions of substantial restructuring of wind waves in the field of inhomogeneous flows: wind-wave amplification during wind decay and vice versa. Examples of such observations are presented, a theoretical model is constructed for the observed phenomenon, and a good agreement is obtained between theory and experiment.  相似文献   

On the vertical electric component of the geomagnetic pulsation field     

D.N. Chetaiev  E.N. Fedorov  S.M. Krylov  V.P. Lependin  V.A. Morghounov  V.A. Troitskaya  K.Yu. Zybin 《Planetary and Space Science》1975,23(2):311-314

The existence of a close correlation between the atmospheric electric field and geomagnetic pulsations in the range of Pc 2–4 is demonstrated experimentally and theoretically (from the horizontal propagation of pulsations). The need to take this into account in any geological-geophysical interpretation of experimental data is stressed.  相似文献   

High-latitude Pc1–2 geomagnetic pulsations and their connection with location of the dayside polar cusp     

O.V. Bolshakova  V.A. Troitskaya  K.G. Ivanov 《Planetary and Space Science》1980,28(1):1-7

The result of investigating high-latitude Pc1–2 pulsations are presented in this paper. They show that these unstructured oscillations are typical in intervals of low magnetic activity for regions of projections of the dayside cusp on the Earth's surface. The morphological properties of these pulsations, namely the character of their diurnal variations and dependence of their amplitude and frequency of occurrence on magnetic activity on different latitudes, suggest methods of utilization for tracing the location of the equatorial boundary of the dayside cusp. It is suggested that Pc1–2 pulsations are generated mainly in the dayside magnetosheath on field lines, crossing the magnetopause and entering in the dayside cusp. The possible mechanism of generation is the ion-cyclotron instability of plasma of finite pressure (β_⊥ ? 1) and with anisotropic temperature (T_⊥ > T_∥).  相似文献   

Variability of the Blazar 4C 38.41 in 2006–2017     

Hagen-Thorn  V. A.  Troitskaya  Yu. V.  Hagen-Thorn  E. I.  Troitsky  I. S.  Savchenko  S. S.  Arharov  A. A.  Efimova  N. V.  Klimanov  S. K.  Volkov  E. V. 《Astronomy Reports》2019,63(5):378-390

The results of multicolor photometric and polarization observations of the blazar 4C 38.41 (Q 1633+382) performed at St. Petersburg State University, the Pulkovo Astronomical Observatory of the Russian Academy of Sciences, Boston University, and Steward Observatory in 2006–2017 are analyzed. Separate variable sources responsible for the observed activity are distinguished, whose power-lawspectra and high degree of polarization confirm their synchrotron nature. The observed color variability of the object (redder when brighter) can be explained by an increase in the contribution to the total emission of a red component with variable flux and a constant relative spectral energy distribution. A close correlation between the optical and gamma-ray light curves is identified, suggesting the same location of the variable sources responsible for the radiation in these bands.

  相似文献   

On the application of a turbulence closure modified model to the description of the density jump evolution in a stably stratified medium     

E. V. Ezhova  S. S. Zilitinkevitch  G. V. Rybushkina  I. A. Soustova  Yu. I. Troitskaya 《Izvestiya Atmospheric and Oceanic Physics》2016,52(3):294-300

The self-similar turbulent density jump evolution has been studied in the scope of a turbulence closure modernized theory which takes into account the anisotropy and mutual transformation of the turbulent fluctuation kinetic and potential energy for a stably stratified fluid. The numerical calculation, performed using the equations for the average density and kinetic and potential energies of turbulent fluctuations, indicates that the vertical profiles of the buoyancy frequency, turbulence scale, and kinetic and potential energies drastically change when the turbulence anisotropy is strong. The vertical profiles of the corresponding energy and spatial discontinuity parameters, calculated at a weaker anisotropy, indicate that similar drastic changes are absent and a qualitative agreement exists with the known analytical solution, which describes the density jump evolution in a freshwater basin and was obtained previously [5, 8] in the scope of a turbulence local-similarity hypothesis applied in combination with the budget equation for the turbulent fluctuation kinetic energy.  相似文献   

Laboratory study of the dynamics of a layer of turbulence excited by standing surface waves     

O. S. Ermakova  S. A. Ermakov  Yu. I. Troitskaya 《Izvestiya Atmospheric and Oceanic Physics》2007,43(1):86-94

The evolution of a turbulent layer excited by standing surface parametric waves is studied experimentally. The time dependence of the depth of the turbulized region is obtained. It is found that the thikness of the layer is described by a nonlinear dependence as distinguished from the previously obtained theoretical results. The dynamics of turbulent-layer embedding is described on the basis of a semiempirical theory and the assumption that the outer scale of turbulence is constant. Satisfactory agreement with experimental data is obtained. In the context of the proposed model, a relationship is found between the quantities characterizing the turbulence and surface waves. The dependence of the steepness of surface waves on the acceleration of the bottom is obtained experimentally. The data obtained in this study can be used for estimation of turbulence generation during a submarine earthquake.  相似文献