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991.
This paper reports laboratory investigations on the absorption spectrum of SiC particles in the 10 μm region. The particles had a mean diameter of 0.31 μm. Our experimental results indicate that a large part of the infrared excess observed in carbon stars may be caused by SiC. 相似文献
992.
993.
J. A. Docobo V. S. Tamazian N. D. Melikian M. H. Eritsian A. A. Karapetian 《Astrophysics》2000,43(2):162-169
The results of photometric and polarimetric observations of the star Μ Cep at Byurakan Observatory are presented. Some interesting
correlations between the parameters of the star’s brightness variation and the degree of polarization of the light are obtained.
It is suggested that the recorded rapid changes in the degree of polarization may result from Μ Cep being a double star.
Translated from Astrofizika, Vol. 43, No. 2, pp. 219-228, April–June, 2000. 相似文献
994.
A.M. Cherepashchuk 《Astrophysics and Space Science》2000,274(1-2):159-175
Various observational appearences of the effects of wind-wind collision for binary stellar systems have been discovered recently
in X-ray, UV, optical, IR and radio ranges. Recent 3D gas-dynamic simulations of the wind-wind collision regions in WR+O,
O+O and symbiotic binary systems allow to understand the physics of wind-wind collision effects, provide interpretation of
observational data and constrain basic parameters of winds as well as those of binary systems.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
995.
996.
997.
998.
999.
Epimetheus, a small moon of Saturn, has a rotational libration (an oscillation about synchronous rotation) of 5.9°±1.2°, placing Epimetheus in the company of Earth’s Moon and Mars’ Phobos as the only natural satellites for which forced rotational libration has been detected. The forced libration is caused by the satellite’s slightly eccentric orbit and non-spherical shape.Detection of a moon’s forced libration allows us to probe its interior by comparing the measured amplitude to that predicted by a shape model assuming constant density. A discrepancy between the two would indicate internal density asymmetries. For Epimetheus, the uncertainties in the shape model are large enough to account for the measured libration amplitude. For Janus, on the other hand, although we cannot rule out synchronous rotation, a permanent offset of several degrees between Janus’ minimum moment of inertia (long axis) and the equilibrium sub-Saturn point may indicate that Janus does have modest internal density asymmetries.The rotation states of Janus and Epimetheus experience a perturbation every 4 years, as the two moons “swap” orbits. The sudden change in the orbital periods produces a free libration about synchronous rotation that is subsequently damped by internal friction. We calculate that this free libration is small in amplitude (<0.1°) and decays quickly (a few weeks, at most), and is thus below the current limits for detection using Cassini images. 相似文献
1000.
In this paper, we derive the scaling laws for different radiating fluids. The studied regimes are relevant for both laboratory astrophysics and High Energy Density Physics. Using Lie groups theory, we obtain scaling laws, the similarity properties and the number of free parameters to rescale experiments. 相似文献