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101.
The interaction of matter and radiation in a hot-model universe 总被引:3,自引:0,他引:3
In this paper we continue the investigation initiated by Weymann as to the reason why the spectrum of the residual radiation deviates from a Planck curve. We shall consider the distortions of the spectrum resulting from radiation during the recombination of a primeval plasma. Analytical expressions are obtained for the deviation from an equilibrium spectrum due to Compton scattering by hot electrons. On the basis of the observational data it is concluded that a period of neutral hydrogen in the evolution of the universe is unavoidable. It is shown that any injection of energy att>1010 sec (red shiftz<105) leads to deviation from an equilibrium spectrum.Translated by Peter Foukal. 相似文献
102.
Conclusions In the Newtonian case we have obtained an isotropic self-consistent distribution of gravitationally interacting point masses which satisfies the transport equation without collisions, and the gravitational equation for an arbitrary powerfunction density distribution =r–s, s<3.For =r–2 the analogous self-consistent solution was obtained for the anisotropic distribution function both in Newtonian and GTR cases.The GTR solutions with =r–2 have central redshifts which increase without limit in accordance with the law 1+zr–1/ as we approach the center. In the isotropic case, they appear to be stable when the mean velocities are much less than the velocity of light u<0.2c, >21.The hydrodynamic GTR solution was found for a perfect gas at constant temperature (but variable T=T(g00)1/2) which also has z for r0.We should like to thank K. Thorne, L. Hazin, and M. Podurets for valuable discussions. K. Thorne was particularly helpful in supplying unpublished results on circular orbits obtained by American authors.Astrofizika, Vol. 5, No. 2, pp. 223–234, 1969 相似文献
103.
The paper suggests an explanation of the deviations from the power law which are observed in frequency spectra of discrete radio sources at decametric wavelengths. It has been shown that a possible mechanism of the deviations is a combined effect of the stimulated and spontaneous scattering of relativistic electrons in the turbulent plasma of a source, as well as ionization energy losses thereof. The distribution function of the relativistic electrons, empirically established in an earlier paper (Braudeet al., 1971) has been derived from the kinetic equation. For a number of discrete sources the turbulence energy density and the plasma concentration are deduced with the aid of experimental data on low-frequency radio spectra.
. , , . , (Braude et al, 1971), . .相似文献
104.
105.
The genesis of local compact segregations of iron sulfide (pyrite) in mudstones at the roof of some coal seams in the Donets Basin (Donbas) is examined. Arguments presented in the work show that sulfides were formed as a result of bacterial sulfate reduction and hydrogen sulfide generation in zones of organic matter concentration. The lack of any signs of influx of alien components testifies to in situ sulfide accumulations at the syngenetic or early diagenetic stage in bottom sediments of the basin. The shape and structure of pyrite segregations suggest that they could be sulfide bioherms occasionally subjected to mechanical deformation in a liquid mud under the influence of gravitational force or external mechanical (possibly seismic) loads. The obtained data can serve as an additional source of information pertaining to the formation conditions of sulfide ore deposits. 相似文献
106.
107.
两次岫岩震群的特征及其预报意义研究 总被引:3,自引:1,他引:2
本文对1988年1月、1999年11月岫岩两次震群的性质及序列特征作了较系统的分析和研究。结果表明:序列各项特征参数及预测指标都显示出了具有明确意义的预报信息。特别是1999年11月前震序的低b值、低h值及多台小震初动符号和波形特征的高度一致性和稳定性都预示着震源区应力的高度集中和稳定,也为短临预报提供了可靠的信息。此外,前震序列的频度分布的时间结构和能量释放的时间过程也明确显示出“密集-平静-发震”和“增强-减弱-发震”的特点。这种临震预报特征与海域地震前震活动的时空结构和时空过程十分相似。本文还讨论了两震群之间特殊部位发生断层贯通的可能性,并给出震级上限的估计。 相似文献
108.
109.
N. Ya. Maksimov 《Geomagnetism and Aeronomy》2006,46(5):635-637
A comparison of the time variations in the geomagnetic field characteristics (the u and aa indices of geomagnetic activity) with the variation in the solar magnetic dipole inclination shows close agreement between these variations. The linear correlation coefficients between the u and aa indices, the u index and solar magnetic dipole inclination, and the aa index and solar magnetic dipole inclination are 0.93, 0.45, and 0.49, respectively. This makes it possible to extend studying the IMF evolution in the 11-year cycle of solar activity to the 170-year period beginning from 1835. It has been indicated that the time variation in the heliospheric current sheet (HCS) surface deviation from the solar magnetic equator plane, calculated based on the actual HCS configuration, is in good agreement with the time variation in the amplitude of the Fourier series second harmonics in a harmonic analysis of the series of daily data on the IMF sign in the vicinity of the Earth. The linear correlation coefficient is 0.9 in this case. 相似文献
110.
R. E. Tatevossian A. Ugalde Zh. Ya. Aptekman A. E. Petrosyan 《Izvestiya Physics of the Solid Earth》2006,42(2):124-131
The possibility to obtain a more complete and unbiased long-term history of seismic shakings over large territories than is explicitly reported from inhabited localities is discussed in the paper. An approach proposed for this purpose consists in complementing the spatial distribution of the macroseismic effect of earthquakes by calculated intensities at localities where information on felt shakings is absent. The calculated intensity is obtained on the basis of data on the epicentral intensity and location of epicenters provided by earthquake catalogs. This approach is applied to the analysis of the history of seismic shaking in Spain. The calculated intensities are shown to be comparable in accuracy with the ordinary practice of intensity determinations at national seismological centers. 相似文献