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991.
Plane-symmetric solutions of Einstein's field equations in vacuum, in the presence of electromagnetic fields and with cosmological constant are explored in null coordinates. The gravitational field of an infinite plane (uncharged and charged both) is thus obtained in a simple and systematic way. The method adopted for these solutions has possibilities of generalization. 相似文献
992.
On thermal-convective instability in a stellar atmosphere with finite Larmor radius and Hall effects
The thermal-convective instability of a stellar atmosphere is considered to include rotation, finite Larmor radius and Hall effects in the presence of a uniform vertical magnetic field. The criterion for monotonic instability is found to be the same even if the above effects are included. 相似文献
993.
Self-similar flows of self-gravitating gas behind the spherical shock wave propagating in a non-uniform atmosphere at rest, taking radiation heat flux into consideration, are investigated. The total energy of the wave is non-constant and can be made to vary slowly with time. 相似文献
994.
Small adiabatic radial oscillations of composite models have been investigated. The effect of central condensation ρc√ρ on the period of pulsation have also been examined. In has been shown that the second moment of mass concentration characterize the periods of pulsation more effectively than central condensation. 相似文献
995.
Detection of two new soft X-ray sources and their identification with the supernova remnants (RNRs) 3C400.2 and MSH 15-56, is reported. From the observed X-ray flux in the 0.7–2.0 keV energy range, the X-ray luminosity of 3C400.2 is derived to be in the range of (2.7–5.3)×1035 ergs s?1 and that of MSH 15-56 in the range of (0.9–1.6)×1035 ergs s?1. If we use the standard adiabatic shockwave model for the SNR's, an age of ~(1.4–3.2)×104 yr is derived for 3C400.2 whereas MSH 15-56 is found to be younger of an age of (5–10)×103 yr. 相似文献
996.
A self-similar flow of a perfect gas behind a strong shock driven out by a propelling contact discontinuity surface moving with time according to an exponential law in the presence of axial component of the magnetic field is investigated. The flow between the shock and the inner-expanding surface is assumed to be isothermal. The infinite electrically conductive and uniform medium has been taken into consideration. 相似文献
997.
Solutions of Brans-Dicke field equations are obtained when the source of the gravitational field is a perfect fluid with pressure equal to energy density and the metric is cylindrically symmetric of Marder-type. Various physical and geometrical properties of the model have been discussed. Finally the solutions have been transformed to the original form of Brans-Dicke (1961) theory and then through unit transformation to a general form. 相似文献
998.
J. B. Singh 《Astrophysics and Space Science》1983,95(2):299-303
An analytical solution for a self-similar isothermal flow behind a radiation driven shock wave in non-uniform medium at rest is investigated using the method of Laumbach and Probstein (1969). 相似文献
999.
J. B. Singh 《Astrophysics and Space Science》1983,92(1):191-195
A self-similar solution, for the equatorial propagation of axisymmetric point explosion into an inhomogeneous ideal gas permeated by a current-free azimuthal magnetic field, are obtained. The model has been considered here in which the magnetic field is proportional tor ?1, but the total energy of the wave is of the increasing order, not constant. 相似文献
1000.
In this paper we have investigated some LRS Bianchi type-V cosmologicla models representing a viscous fluid distribution with a null electromagnetic field and streaming neutrinos. Various physical and kinematical features of these models have also been explored. 相似文献