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31.
We suggest a method for extracting important cosmological information from observational data on galaxy proper motions on
the celestial sphere. These data can be used to reconstruct the three-dimensional velocities of galaxies relative to the cosmicmicrowave
background (peculiar velocities), and to separate the Hubble and peculiar components of the observed redshifts in a large
volume for the first time. As a result, it is possible to determine the Hubble constant accurately and independently using
the radial velocities of comparatively close galaxies (up to 50 Mpc), and to determine distances to the galaxies and the mass
distribution in the neighborhood of the Local group of galaxies. The proposed task may be solved using the future “Millimetron”
space radio interferometer. 相似文献
32.
New Estimates of the Merger Rate of Primordial Black Holes with Allowance for Clustering Dark Matter
Astronomy Letters - The merger rate of primordial black holes (PBHs) is numerically estimated by taking into account the gravitational interaction of PBHs with clustering cold dark matter (DM). The... 相似文献
33.
A. V. Petlenko Yu. A. Kopytenko V. A. Martines V. A. Pilipenko V. S. Ismagilov 《Geomagnetism and Aeronomy》2011,51(5):584-598
An analysis of the BEAR experiment and Polar satellite data showed that several ionospheric sources could act almost simultaneously
in the area of Pi2-type geomagnetic pulsations. The aim of this study is to locate these sources and determine their coherence
in the narrow-frequency band of (6–10) × 10−3 Hz. By using gradient analysis methods, we revealed the local sources of oscillations coherent (phased), that allows one
to treat their contributions as manifestations of the fine structure of the field of Pi2 pulsations. 相似文献
34.
Paleomagnetic studies of Quaternary deposits from the Malyi Kut rock sequence (Krasnodar krai, western part of the Taman Peninsula) in two time intervals of Late Pleistocene are carried out. The Malyi Kut sequence is a marine terrace of the Baku age, which is embedded in the disturbed marine Sarmatian deposits. The terrace of the Bakinian age nests the Karangat marine terrace. The presence of the marine molluscan fauna in the both terraces enables reliable dating of the studied deposits. The composition, grain size, and concentration of ferromagnetic fraction present in the studied rocks are investigated by a set of rock magnetic methods. The directions of natural remanent magnetization (NRM) are studied, and the reliability of their isolation is estimated. The results are compared with the paleomagnetic records of NRM in the rocks of the parallel coeval sections of the Tuzla (Taman Peninsula) and Roxolany (Ukraine). This correlation suggests that the studied rock sequences recorded the Mono Lake geomagnetic excursion. 相似文献
35.
V. B. Belakhovsky V. A. Pilipenko S. N. Samsonov D. Lorentsen 《Geomagnetism and Aeronomy》2016,56(1):42-58
Simultaneous morning Pc5 pulsations (f ~ 3–5 mHz) in the geomagnetic field, aurora intensities (in the 557.7 and 630.0 nm oxygen emissions and the 471.0 nm nitrogen emission), and riometer absorption, were studied based on the CARISMA, CANMOS, and NORSTAR network data for the event of January 1, 2000. According to the GOES-8 satellite observations, these Pc5 geomagnetic pulsations are observed as incompressible Alfvén waves with toroidal polarization in the magnetosphere. Although the Pc5 pulsation frequencies in auroras, the geomagnetic field, and riometer absorption are close to one another, stable phase relationships are not observed between them. Far from all trains of geomagnetic Pc5 pulsations are accompanied by corresponding auroral pulsations; consequently, geomagnetic pulsations are primary with respect to auroral pulsations. Both geomagnetic and auroral pulsations propagate poleward, and the frequency decreases with increasing geomagnetic latitude. When auroral Pc5 pulsations appear, the ratio of the 557.7/630.0 nm emission intensity sharply increases, which indicates that auroral pulsations result from not simply modulated particle precipitation but also an additional periodic acceleration of auroral electrons by the wave field. A high correlation is not observed between Pc5 pulsations in auroras and the riometer absorption, which indicates that these pulsations have a common source but different generation mechanisms. Auroral luminosity modulation is supposedly related to the interaction between Alfvén waves and the region with the field-aligned potential drop above the auroral ionosphere, and riometer absorption modulation is caused by the scattering of energetic electrons by VLF noise pulsations. 相似文献
36.
V. A. Rashidov O. V. Pilipenko V. M. Ladygin 《Journal of Volcanology and Seismology》2014,8(3):168-182
We studied the petrophysical and magnetic properties of dredged rocks that compose the edifices of five active submarine volcanoes in the Pacific Ocean, viz., the Fukujin, Esmeralda, Kovachi, and Simbo at island arcs, and Ile des Cendres in a marginal sea. We measured the standard petrophysical and magnetic characteristics and performed three kinds of thermomagnetic analysis as well as an electron-probe analysis. Comparative analysis of magnetic properties in rocks showed that they are strongly differentiated by the value of natural remanent magnetization and of magnetic susceptibility. The greatest values are shown by the Esmeralda aphyric basaltic andesites, the lowest occur in the Ile des Cendres xenoliths. The principal carriers of magnetization in the rocks are grains of unaltered and/or oxidized titanomagnetite with varying domain structures. All the samples are magnetically isotropic. 相似文献
37.
38.
A unified theory of low frequency instabilities in a two component (cold and hot) finite-β magnetospheric plasma is suggested. It is shown that the low frequency oscillations comprise two wave modes : compressional Alfvén and drift mirror mode. No significant coupling between them is found in the long-wave approximation. Instabilities due to spontaneous excitation of these oscillations are considered. It is found that the temperature anisotropy significantly influences the instability growth rate at low frequency. A new instability due to the temperature anisotropy and density gradient appears when the frequency of compressional Alfvén waves is close to the drift mirror mode frequency. The theoretical predictions are compared in detail with the Pc5 event of 27 October 1978 observed simultaneously by the GEOS 2 satellite and the STARE radar facility. It is shown that the experimental results can be interpreted in terms of a compressional Alfvén wave driven by the drift anisotropy instability. 相似文献
39.
O. A. Pokhotelov M. Parrot E. N. Fedorov V. A. Pilipenko V. V. Surkov V. A. Gladychev 《Annales Geophysicae》1995,13(11):1197-1210
A review is presented of the effects influencing the ionosphere which are caused by acoustic emission from different sources (chemical and nuclear explosions, bolides, meteorites, earthquakes, volcanic eruptions, hurricanes, launches of spacecrafts and flights of supersonic jets). A terse statement is given of the basic theoretical principles and simplified theoretical models underlying the physics of propagation of infrasonic pulses and gravity waves in the upper atmosphere. The observations of “quick” response by the ionosphere are pointed out. The problem of magnetic disturbances and magnetohydrodynamic (MHD) wave generation in the ionosphere is investigated. In particular, the supersonic propagation of ionospheric disturbances, and the conversion of the acoustic energy into the so-called gyrotropic waves in the ionospheric E-layer are considered. 相似文献
40.
O. M. Chugunova V. F. Pilipenko M. Engebretson A. S. Rodger 《Geomagnetism and Aeronomy》2006,46(1):64-73
The diumal variations in the parameters of Pc3 (20–60 mHz) and Pc4 (10–19 mHz) pulsations at latitudes of the dayside cusp and polar cap have been studied using data of the magnetic stations of the trans-Antarctic meridional profile for the time interval from January to March 1997 (local summer) under weakly disturbed geomagnetic conditions (AE ≤ 250 nT). The technique for estimating pulsation parameters is based on the separation of the wave packets and noise. The diumal variations in the hourly average parameters of the wave packets in the Pc3 and Pc4 bands and noise in the Pc3-4 band (10–60 mHz)—the average number of wave packets, energy of wave packets and noise, and energy of a single wave packet—turned out to be different for the stations located deep in the polar cap (Φ ～ 87°) and at the latitudes of the dayside polar cusp (Φ ～ 70°) and auroral oval (Φ ～ 66°). Several sources of pulsations caused by different channels of wave energy penetration into the magnetosphere through the dayside cusp, dayside magnetopause, and dawn flank of the magnetotail apparently exist at high latitudes. 相似文献