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871.
T. Dixit 《Astrophysics and Space Science》1989,152(1):125-130
In this paper considering the turbulent dusty flow of an incompressible viscous fluid which is nearly isotropic and spatially homogeneous with an extra vector argument (rotation symmetry) the expression for acceleration covariance in the presence of the Coriolis force has been derived and solution has been obtained in terms of defining scalars. 相似文献
872.
Veeder GJ Hanner MS Matson DL Tedesco EF Lebofsky LA Tokunaga AT 《The Astronomical journal》1989,97(4):1211-1219
We report 10 micrometers infrared photometry for 22 Aten, Apollo, and Amor asteroids. Thermal models are used to derive the corresponding radiometric albedos and diameters. Several of these asteroids appear to have surfaces of relatively high thermal inertia due to the exposure of bare rock or a coarse regolith. The Apollo asteroid 3103, 1982 BB, is recognized as class E. The Jupiter-crossing Amor asteroid 3552, 1983 SA, is confirmed as class D, but low albedos remain rare for near-Earth asteroids. 相似文献
873.
In the computation of density perturbation in inflation it is conventional to assume the inflation field to be in the vacuum state. There are, however, some advantages in relaxing this assumption. In an earlier paper we have estimated the density perturbations in a Gaussian coherent state using a toy-model. Here we extend this work by doing an exact analysis of this problem. The advantages of this method is discussed and the results are compared with earlier results 相似文献
874.
The Moon's umbral shadow, tangentially penetrating the Earth's atmosphere, appreciably reduces the brightness of the twilight sky at points located under the shadow axis. This should yield favourable conditions for observation of the zodiacal light for small altitudes of the Sun below the horizon. The location of the projection of the Moon's shadow axis at the Earth's surface under the above conditions is calculated for the case of the total solar eclipse of 30 June, 1992. 相似文献
875.
The equation of transfer for interlocked multiplets has been solved exactly by the method used by Busbridge and Stibbs (1954) for exponential form of the Planck functionB
v
(T)=b
0+b
1
e
–. 相似文献
876.
An approximate solution of the transfer equation for coherent scattering in stellar atmospheres with Planck's function as a nonlinear function of optical depth, viz.,
相似文献
877.
The Wilcox Solar Observatory at Stanford University houses one of the International Research on the Interior of the Sun (IRIS) network observing stations. The instrument has observed the global oscillations of the Sun continually since it was installed in August 1987. Each site and instrument are different; here we report the details unique to the Stanford site. 相似文献
878.
The general equation for radiative transfer in the Milne-Eddington model is considered here. The scattering function is assumed to be quadratically anisotropic in the cosine of the scattering angle and Planck's intensity function is assumed for thermal emission. Here we have taken Planck's function as a nonlinear function of optical depth, viz.,B
v(T)=b
o+b
1
e
–. The exact solution for emergent intensity from the bounding face is obtained by the method of the Laplace transform in combination with the Wiener-Hopf technique. 相似文献
879.
K. P .Raju J. N. Desai T. Chandrasekhar N. M. Ashok 《Journal of Astrophysics and Astronomy》1991,12(4):311-317
The line intensity of the green coronal line and the continuum intensity are derived from the filter and white light photographs of the solar corona obtained during the 1980 total solar eclipse. Ratio of the line to continuum intensity is plotted against the radial distancer(=R/R0,R 0 is the solar radius), in various position angles. A simple model assuming an electron density dependence of the line and continuum intensities suggests a dominant collisional mechanism for the excitation of the line in the innermost regions (~ 1.4R 0). The measured line to continuum ratio tends to a constant value at different radial distances in different position angles. The constancy of the measured line to continuum ratio indicates significant radiative excitation beyond 1.4 R0, in some of the position angles. 相似文献
880.
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