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1.
It is found that the relationship between the potential energy and the moment of the inertia independent of the radial mass distribution obtained earlier for the sphere also holds in the case of the ellipsoidal mass distribution for the ellipsoid of rotation.The possibility of application of the energy virial relations for solution of the evolutionary problems of the gravitating gaseous sphere, with the help of the relationship found earlier, is demonstrated. The physical conditions on the gaseous sphere boundary are introduced. The existence of two branches of evolution, the proton one and the electron one, is established. The problem of the gravitational contraction velocity during sphere evolution is solved. The relationship between the boundary temperature and the gaseous sphere radius as well as between the luminosity and the body mass is obtained. Some limiting relations for the final stage of the gaseous sphere evolution are found.
, , , . . . — . . , . .
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1.40M . C12+C12Mg24+. Bruenn (1972) . , ( ), . , URCA . ( , ) . .  相似文献   

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Some attempts of polarimetric sounding of Comet Halley will be undertaken from the flyby probes. In order to facilitate the final planning and the future interpretation of these experiments we have done a thorough analysis of practically all available polarimetric observations. An emphasis is made on interpretation attempts and their discussion. The results of the phase dependence of polarization investigations are presented covering a wide range of phase angles . The chief peculiarities of this dependence are: maximum polarization at = 90, diminishing through zero at 20, negative values up to several per cent and a final growth to zero at zero . A division into gaseous and dusty comets on polarimetric basis is revealed. The wavelength dependence of polarization is discussed. The numerous results of detailed polarimetry are compared to the negative results of attempts to detect the elliptical polarization. New observational problems arising from the evidence given by the negative polarization at small phase angles and by the opposition effect recently discovered are discussed.  相似文献   

6.
The high-frequency electromagnetic and gravitational radiation from a relativistic particle falling into a Kerr and Schwarzschild black hole is considered. The spectral and angular distributions of the radiation power are calculated by the WKB technique to Teukolsky's equations. The spectra obtained have a characteristic exponential cut-off at the frequency = char. which is proportional to the particle Lorentz factor =(1–v 2/c2)–1/2. At the frequencies as low as those compared with char. both electromagnetic and gravitational spectra are flat. The amount of the energy emitted in the low-frequency modes of the radiation depends strongly on the radiation spin. It is proportional to ln for the electromagnetic and to 3 for the gravitational radiation.  相似文献   

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Some asymptotic solutions in the restricted problem of three bodies by L. G. Lukjanov.
Some particular solutions of the plane restricted problem of three bodies in the form of Liapunov's series are obtained. These solutions asymptotically approach the Lagrange solutions. Convergence is proved.
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9.
2800 Mgii (. 1). (N +/N 11000) , , (N +/N 110). , . —, , . — . : ; 0.002 1 , 0.1 ; () 100 –3; ; ; , 10 ; 10–4 1 . 2800 Mgii .  相似文献   

10.
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The structure of rotating magnetic polytropes is considered in Roche approximation. Investigation of the influence of poloidal as well as toroidal magnetic fields on the conditions of the beginning of matter outflow due to rotational instability is carried out. The influence of the turbulent convection and twisting of magnetic force-lines on the time of smoothing of differential rotation is considered. The estimate of the magneto-turbulence energy generated by differential rotation is presented. Both maximum possible energy output and duration of the quasi-statical evolution phase up to the appearance of hydrodynamic instability due to the effects of general relativity are calculated for supermassive magnetic polytropes of index three with uniform or differential rotation. The radius-mass relation is obtained for supermassive differentially-rotating magnetic polytropes referring to the longest part of the quasi-statistical evolution stage; some consequences are pointed out, including the period-luminosity relation.The evolution of the considered models of supermassive rotating magnetic polytropes with different character of rotation and different geometry of a magnetic field is discussed.The results obtained are summarized in the last section.


English translation will appear in the next issue ofAstrophys. Space Sci.

Receipt delayed by postal strike in Great Britain  相似文献   

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1937 - (, 1938). , , , , . , . . (, 1938), , . - (, 1938; Szebehely, 1967)., , . . - (, 1938), . — — . , , . , . . , . , , . . (, 1944). , .
In 1937, the Celestial Mechanics and Cosmogony section of the Sternberg State Astronomical Institute undertook the task of evaluating the Gylden-Moulton hypothesis on the origin of the Gegenshein from the standpoint of celestial mechanics. That investigation, which the authors themselves considered preliminary, contains nonetheless a series of important results. For example, G. N. Duboshin showed that in the planar, circular, restricted three-body problem, periodic motion of finite amplitude in the neighborhood of a collinear libration point is unstable according to Lyapunov's criterion both in the proper and in the orbital sense. The latter result is incompatible with the above named hypothesis, and thus appears as one of the serious objections among the many known negative conclusions relative to the existence of the Gylden-Moulton cluster.Unfortunately, most of the specific problems which arose in the above named research have not been considered since. One of these, the problem of the stability of three-dimensional periodic orbits in the neighborhood of a collinear libration point is solved in the present paper, within the limits of the three-dimensional, circular, restricted, three-body problem. Major attention is given to the investigation of stability in the orbital sense, since in the proper sense all orbits are unstable according to Lyapunov theory. It is shown that in order to resolve the question of stability, it is sufficient to consider the equations in their variational form. Analysis of the roots of the corresponding characteristic equations determines the orbital stability of planar and three-dimensional solutions, which later can be confirmed by calculation of the characteristic exponents appearing in the periodic solutions of the N. A. Artemiev method. Finally, the possibility of conditional stability in the linear approximation is proved.
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. . ,e, , . . e, . , .
Stability of the librational triangular points of the three-dimensional elliptic restricted three-body problem is studied. The problem is solved in the non-linear statement at the small values of eccentricity.For all values ofe, , besides ones which correspond to the resonances of the third and the fourth order the librational points are stable taking into account the terms up to the fourth order in the normal form of the Hamiltonian function of the perturbed motion.At sufficiently smalle and the non-stability in sense of Liapunov has been proved. The approximate equations of the boundary of the stability area in the planee, has been obtained. The cause of the non-stability is an equality of the rotational period of the principal attracting masses in the elliptic orbit and the period of oscillation of indefinitely small mass along the direction perpendicular to the plane of their motion.
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17.
Data on a statistic derived from the angular covariance function show that (contrary to the claim of Peebles that galaxies are distributed continuously with no distinct scales), superclusters and the maximum size of clusters are probably defined at scales of 15 and 2.0h –1 Mpc. This suggests some stepped-density profile like the idealized models of de Vaucouleurs and Wertz: consideration is therefore given to a semi-continuous hierarchy in which there are galaxies outside clusters, clusters outside superclusters etc. Theories of the origin of clustering by gravitational clumping and the escape of galaxies from clusters suggests the hypothesis that the average mass (m g) of galaxies outside clusters is smaller than that of those inside (=fractionf of the total), a hypothesis supported by results on the continuity of the angular and spatial covariance functions. In a semi-continuous hierarchy, the overall packing fractionf e and the fraction (1-f) of galaxies outside clusters both appear to increase as the distancer from a local origin increases, because a line-of-sight to greater depths intersects systems of the hierarchy of continually greater size (R i). If the hypothesis is valid thatm g inside clusters is slightly larger thanm g outside, the apparent effect is to makem g systematically distance-dependent from a local origin with and 10.3. No direct data on galaxy masses exist to refute such a small trend, but since the absolute magnitudes of galaxies are known to be correlated (very weakly) with their masses, a semi-continuous hierarchy has a location-dependent luminosity function, (M). Within uncertainties as to the steepness of (M) at the bright end, the model is consistent with optical number counts to a limiting photographic magnitudem pg (isotropic slope,q=0.6; semicontinuous modelq=0.64; observation,q=0.67±0.03, standard error.) this removes the discrepancy between the determinations by de Vaucouleurs and Sandageet al. of the thinning factor (1.7). Predictions of the semi-continuous model are made which are at present observationally feasible to carry out. In particular, it is predicted thatq(20<|M|<22)/q(14<|M|<19)2(±0.2).  相似文献   

18.
Periodic orbits of stars in axisymmetrical nearly spherical stellar systems have been investigated. Generating orbits have been found among periodic ones relating to the spherically-symmetrical field. The linear approximation appears to be insufficient for constructing periodic trajectories. Possible variants of the generating periodic solutions have been found, which give rise to disturbed periodic orbits in the second approximation.
, . - . , . , .
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19.
We report the observation and interpretation of a correlated type III burst emitted from distant sources on the Sun. The angular separation between the distant sources is as large as 26 or 106 km. There was an active region 30° behind the limb, and it is believed that the type III burst emission originated from activity in this region. The implications of the locations of the correlated sources with regard to the geometry of the magnetic structures involved in the flare process are discussed.On leave from Indian Institute of Astrophysics, Kodaikanal, India.  相似文献   

20.
, ( ). n =3–5, T e =4T b (1 + ), - ( ) ,T b - . , . , . W H , ,n =3, =1. n =3–5(E), (E) , , = 1 – (), |()| < 1, |(E)| < 1. 3 273.  相似文献   

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