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Résumé Le présent travail est une continuation d'un autre, publié plus tôt (Doubochine, 1970). On montre ici, que les propriétés des mouvements Lagrangiens et Euleriens établies en mécanique céleste classique sont vraies aussi dans les cas plus généraux, envisagés dans le travail indiqué. On montre de plus, que les trajectoires des points en ces mouvements en axes absolus sont les spirales infinies s'enroulant sur les surfaces des cylindres curvilignes infinis.
-- , (, 1970). , , , , , , , . , , , , .
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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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I I (, 1976). I :I I I I I I I (I) I I . I . , I I .
Euler solutions in the problem of the translatory-rotary motion of three rigid bodies
The present paper is a continuation of the article (Vidyakin, 1976) in which we proved the existence of Lagrange (triangle) solutions in the general problem of the translatory-rotary motion of three absolutely rigid bodies.In particular, we have found the conditions for the existence of Lagrange solutions in the case when all the bodies possess a symmetry with respect to three mutually perpendicular planes both in respect to the distribution of matter and in respect to the outward form. In this case the bodies effect simple translations along with the centres of the masses without rotation (in Lyapunov's system of coordinates).If the rigid bodies possess a symmetry in respect to the axis and to the plane, perpendicular to this axis, then the Lagrange solutions of the three floats (Duboshin, 1973), three spokes (Kondurar, 1974), three shafts (Vidyakin, 1976) types are admitted, as well as the solutions in the cases of combinations of the float, spoke and shaft-bodies (Vidyakin, 1976).Those solutions exist of certain conditions, imposed on the structure, orientation and rotation of the bodies, are observed.In the general case (there) exist particular solutions which we have termed as Near-Lagrangian.The present paper is to prove the existence of Euler (rectilinear) solutions in the problem of the translatory-rotary motion of three rigid bodies, assuming that the elementary particles of the rigid bodies are mutually attracted according to the Newtonian law.In particular, we have found the conditions for the existence of Euler solutions in the case when all the bodies possess a symmetry in respect to three mutually perpendicular planes both in respect to the distribution of matter and in respect to the outward form. In this case the bodies are so disposed in the uniformly rotating coordinate system that two symmetry planes concur while the centres of the masses are disposed on one straight line.In particular, if the bodies possess a symmetry in respect to the axis and to the plane perpendicular to this axis, then the Euler solutions of the three floats (Duboshin, 1973), three spokes, three shafts types as well as solutions in the cases of combinations of float-, spoke- and shaft-bodies and spheres, either homogeneous or possessing a spherically symmetric distribution of densities, are admitted.The paper gives exact solutions for the cases when the attraction force function of the bodies has an approximate expression.
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(Kilyachkoet al., 1978) , . l ( I II). (Kilyachkoet al., 1978) : (1) 800 Å , , UV Cet. EV Lac; (2) UV Cet EV Lac 8000 Å , ; (3) 8000 Å . — MO-KS; (4) 1–3 m.  相似文献   

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qp qz : (1) -, qi , (2) - (R=0.01–0.1R ) (3) - . qs. (1) - 0.1 10–4 cm –2, . - . (2) 108 . . 1042–43 , (25 ). 10% - (0.1 ). , , , , , . . (3) , , - . . (2×1041 ) (1021 ). - 1038–1039 , 0.25 . , , qq . - , , .
The following three mechanisms of generation of gamma-ray bursts at advanced phases of stellar evolution are considered; (1) gamma-ray bursts as a result of absorption of neutrino propagating through the envelope of a collapsing star, (2) gamma-ray burst due to thermal radiation of external layers of a compact star (R=0.01–0.1R ) heated by powerful shock wave, and (3) gamma-ray burst as a consequence of possible ejection of matter from neutron star at some active phases of its evolution. In the case (1) the gamma-ray flux at the top of the Earth's atmosphere is about 10–4 (0.1 MeV photons) cm–2, if a collapsing star is at Galactic distance (10 kpc). It is considerably less than observed one. The observations of such gamma-bursts however would be an important supplement to the direct detection of neutrino radiation from collapsing stars. In the case (2) external layers of a star are heated up to 108 K. As a result we have a short pulse of thermal radiation with total energy of the order of 1042–43 erg. The main fraction of the radiation is in the X-ray ( 25 keV), about 10% of total energy being radiated in gamma-ray ( 0.1 MeV). The energy of such a burst is sufficient for explaining observed gamma-bursts provided the supernova outburst probably takes place in our Galaxy and as a result we have some trouble with explanation of observed frequency and spectra of gammabursts. In the case (3) ejection from neutron star of chemically nonequilibrium matter results in the intensive gamma-radiation in consequence of superheavy nuclei fission followed by beta-decays and radiative captures of free neutrons. The ejection of matter from neutron stars may be connected with observed jumps of pulsar's periods. The total ejected mass ( 1021 g) can be evaluated from increase of kinetic energy ( 2×1041 erg.) of Crab nebula filaments. The resulting theoretical energy of gammabursts is of the order of 1038–39 erg. It is in accordance with observations provided the mean distance of gamma-ray sources is about 0.25 kpc. Contrary to the supernova-outburst mechanism in this case we have probably no troubles with frequency and spectra of gamma-bursts. Among the three mechanisms considered above ejection of matter from neutron stars seems to be a more suitable one for explanation of observations.
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Stability of the libration points of a rotating triaxial ellipsoid   总被引:1,自引:0,他引:1  
The problem of stability of the equilibrium points (the libration points) in the problem of motion of a mass point in the neighbourhood of a rotating triaxial ellipsoid is investigated in the strict sense.In the plane of parameters, depending on the form and dynamical characteristics of the ellipsoids, the regions of stability and instability of the libration points are obtained.It is shown that the libration points of the ellipsoids, the form and dynamical characteristics of which are close to the planets of the solar system, are stable.
( ) . , , . , , , .
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. . . , , m 1, m2, m3, n ( .
The conditions of stability of the constant libration solutions of the general three-bodies problem obtained by E. Routh through investigation of the linearized perturbed motion equations are analised. To the values of the masses of the three bodies which satisfy boundary conditions of the region of stability the locus of all corresponding centers of masses is laid down in accordance with. It occurs that this locus is a circle, its centre coinciding with the geometric centre of the trianglem 1, m2, m3 and its radius being a function of exponent in the law of attraction of the bodies. The motion may be stable only if the centre of masses of the bodies lies outside the circle mentioned above. In the case of the Newtonian law of attraction the radius of this circle equals 0,943 |rmax| where |rmax| is a distance of the vertex from the centre of the trianglem 1, m2, m3. Thus stability is possible (if it is generally possible) inside a very small region in this case.
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The gravity potential of an arbitrary bodyT is expanded in a series of spherical harmonics and rigorous evaluations of the general termV n of the expansion are obtained. It is proved thatV n decreases on the sphere envelopingT according to the power law if the body structure is smooth. For a body with analytic structure,V n decreases in geometric progression. The exactness of these evaluations is proved for bodies having irregular and analytic structures. For the terrestrial planetsV n =O (n –5/2).
I I V n IV n I . . IV n I . I. IV n =O(n –5/2 )
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The empirical evidence for a connection between type and relative angular momentum of galaxies is reviewed and some constraints for the theoretical explanation are discussed.
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