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1.
Г. Н. Дубошин 《Celestial Mechanics and Dynamical Astronomy》1970,2(4):454-466
(, 1969). ( ), ( ), , , . , (=), , , .. , . , , - ( ), ( ). , .
This paper is a continuation and a generalization of one published earlier (Duboshin, 1969): it discusses the problem whether there exist the Lagrangian and the Eulerian solutions of the generalized three-body (material points) problem. Every point in this generalized problem acts on another, one with a force (attractive or repulsive) directed along the straight line passing through these points, and in an arbitrary manner depending on time, mutual distance and its derivatives, the first and the second. Here, generally speaking, the third axiom of dynamics (law of action and reaction) is not presupposed as fulfilled, that is, it is supposed that every two material points interact in a different way.This most general assumption being made, we establish the conditions which must dictate the laws of the interactions, so that the three points can always remain at the apexes of the equilateral triangle (Langrangian solution), or remain always on a straight line (Eulerian solution).The author believes that such general treatment of the three-body problem can be useful for theoretical studies in celestial mechanics and also for practical applications in the study of isolated stellar systems.相似文献
2.
Max K. Wallis 《Astrophysics and Space Science》1973,20(1):3-18
The interaction processes governing the penetration of the interstellar gas into the solar neighbourhood are re-examined — as well as photo-ionization and charge-exchange processes, proton elastic collisions and electron ionizations help reduce the nearby gas densities. The total destruction rate varies little during the solar cycle, by perhaps 10%. Particle heating, particularly via the elastic collisions, determines the gas characteristics in the gravitationally focussed tail—enhanced H-density is prevented, while the He-tail is effectively hotter than 103 K.Termination of the solar wind is rediscussed in the light of both electron heating and the stronger gas/plasma interaction. The spiral interplanetary field is taken to break up and the subsonic plasma flow to be controlled by the pressure of slowly cooling electrons. The terminating collisionless shock is then, if it exists at all, very weak (M
1<1.4), subcritical, and energetically unimportant. Cosmic rays are little affected by this sonic transition, but at least the electron component should be modulated by plasma turbulence throughout the ionizing flow.
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3.
I I I : Mgas<0.04 Mcor. - . , . 相似文献
4.
-- () ., , , , , . , , . , . 相似文献
5.
, . 2.7°- . . . E3×1019 (1.6) . 相似文献
6.
, , , , . , , . , , - - ( , ..). - . 相似文献
7.
, (DM) (RM). , DM RM N
e
= n
e
ds. M
e
= n
e
H cos ds ; . Lerche (1970a, b) , DM RM N
e
M
e
. . 相似文献
8.
, . , , . , , -, This article investigates the dynamics of a system for damping the nutating motion of a spin-stabilized satellite. The equations of motion of the satellite-damper system are derived omitting consideration of the influence of external torques. The conditions of stability of the stationary spinning are obtained and the optimal parameters of the satellite and the damper ensuring a maximal rate of damping of the nutation motion are determined. 相似文献
9.
V. I. Ferronsky S. A. Denisik S. V. Ferronsky 《Celestial Mechanics and Dynamical Astronomy》1979,20(1):69-81
The applicability of the properties of central configurations proceeding from the many-body problem to study of gaseous sphere cloud evolution during its gravitational contraction is justified. It is shown that the product runs to a constant value in the asymptotic time limit of simultaneous collision of all the particles of the cloud where is a form-factor of the potential energy and is a form-factor of the moment of inertia.The spherical bodies as well as ellipsoids of rotation and general ellipsoids with a one-dimensional mass distribution (k),k[0, 1] are found to possess the property =const.
. , - , , ., , - =const., , (k),k[0, 1].相似文献
10.
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.
( ) . , , . , , , .相似文献
11.
, . . . (10R
) ( 10 000R
). NGC 5457, NGC 6946 NGC 5236. , , II I . . . , . . 1050÷1052 , . 相似文献
12.
А. П. Маркеев 《Celestial Mechanics and Dynamical Astronomy》1973,8(2):307-322
. . ,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.相似文献
13.
Constantin Kholchevnikov 《Celestial Mechanics and Dynamical Astronomy》1972,6(2):214-220
The potential of a body of revolution is expanded in a series of spherical functions. It is proved that for a body of smooth structure the coefficients of expansion decrease in a power law.
. , .相似文献
14.
The most characteristic features of H-R diagrams of blobular clusters are summarized with particular regard to the position and the extension of the horizontal branch. A comparison of observations with theory in the two cases of evolution with and without mass loss is then shortly given.A preliminary approach to the evolution of models with large mass fractions (q
0) in the helium cores is presented. Inhomogeneous equilibrium models with double energy sources have been computed in a range of values ofq
0 and of the total mass referring to possible horizontal-branch stars.
Riassunto Sono indicate le principali caratteristiche dei diagrammi H-R degli ammassi globulari con particolare riferimento alla posizione ed alla estensione del ramo orizzontale. Sono esaminate relazioni tra la teoria ed i parametri indicati nei due casi di evoluzione con e senza perdita di massa.E' presentata infine una analisi di modelli con un'alta frazione di massa nel nucleo di elio (q 0). I modelli di equilibrio, non omogenei ed a doppia sorgente di energia, sono stati calcolati in un intervallo di valori diq 0 e della massa totale che sono in relazione alla regione delle stelle del ramo orizzontale.
- . . . q 0 . q 0 .相似文献
15.
V. I. Ferronsky S. A. Denisik S. V. Ferronsky 《Celestial Mechanics and Dynamical Astronomy》1979,19(2):173-201
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.
, , , . . . — . . , . .相似文献
16.
P. S. Goraya 《Astrophysics and Space Science》1981,78(2):419-425
The photoelectric spectrophotometric scans of the Be stars Gem, Ori, Mon and CMa have been analyzed to find out few stellar parameters. The absolute energy distributions of these stars in the wavelength range 350–750 nm have been given. Their effective temperatures and gravities have been estimated from comparisons with non-LTE model atmospheres. The stars Gem and Mon have been found to have Balmer discontinuities in emission. The excess emission in the region 620–750 nm has been observed for Mon and CMa. The evolutionary aspects of these stars are discussed and their masses have been estimated. 相似文献
17.
18.
Г. А. Гурзадян 《Astrophysics and Space Science》1977,46(2):471-484
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, , , S
Mg. , . , . , ( , ..). B5 B0; (<1%). 相似文献
19.
. . .
, 相似文献
Transfer of resonance radiation in infinite medium is considered as a process of random walks of photons. Close relation is shown to exist between the problems of transfer of line radiation and the stable distributions of the probability theory. This relation is used as a basis of a new method for the investigation of the asymptotic properties of the radiation field far from the sources.
, 相似文献
20.
A. G. Sokolsky 《Celestial Mechanics and Dynamical Astronomy》1978,17(4):373-394
Orbital stability of quasiperiodic motions in the many dimensional autonomic hamiltonian systems is considered. Studied motions are supposed to be not far from equilibrium, the number of their basic frequencies may be not equal to the number of degrees of freedom, and the procedure of their construction is supposed to be converged. The stability problem is solved in the strict nonlinear mode.Obtained results are used in the stability investigation of small plane motions near the lagrangian solutions of the three-dimensional circular restricted three-body problem. The values of parameters for which the plane motions are unstable have been found.
. , , . . , . , .相似文献