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, . () . , , , . ( ), , , . . (2.7). ( 1 k 1 ,V — , — .) (k 1) (k) §2 ( (2.14)). , (3.6) (3.4), (3.8) . (3.9)–(3.13) ( (3.9), (3.10) (3.11) , (3.12)–(3.13) ). (3.14), (3.16)–(3.19). - . (3.15). ( (4.14)–(4.15)). (4.23)–(4.25). (4.26)–(4.28). §5. , . ((5.5)–(5.6)). , . (5.10) .  相似文献   

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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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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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Resume On étudie la stabilité des solutions périodiques d'un couplage de systèmes linéaires au voisinage de résonances. Les valeurs propres distinctes k de la matrice du système linéaire non perturbé sont telles que kj=iq pour tout couple [k, j]; i=–1, q est un nombre entier, la fréquence de la solution. Une application est faite pour un système à trois degrés de liberté au voisinage de la résonance 221.
Hamiltonian systems in the neighbourhood of an equilibrium solution. II:The stability of periodic solutions
The stability of the periodic solutions for an Hamiltonian system is investigated. Here the distinct eigen values k of the matrix of the unperturbated linear system are such that kj=iq for any [k, j]; i=–1, q is an integer, is the frequency of the periodic solution. An application is made for a system with three degrees of freedom, near the resonance 221.
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One-hundred fifty-six large-scale enhancements of X-ray emission from solar active regions were studied on full-disk filterheliograms to determine characteristic morphology and expansion rates for heated coronal plasma. The X-ray photographs were compared with H observations of flares, sudden filament disappearances, sprays and loop prominence systems (LPS). Eighty-one percent of the X-ray events were correlated with H filament activity, but only forty-four percent were correlated with reported H flares. The X-ray enhancements took the form of loops or arcades of loops ranging in length from 60 000 km to 520 000 km and averaging 15 000 km in width. Lifetimes ranged from 3 hr to >24 hr. Event frequency was 1.4 per day. X-ray loop arcades evolved from sharp-edged clouds in cavities vacated by rising H filaments. Expansion velocities of the loops were 50 km s-1 immediately after excitation and 1–10 km s-1 several hours later. These long-lived loop arcades are identified with LPS, and it is suggested that the loops outlined magnetic fields which were reconnecting after filament eruptions. Another class of X-ray enhanced loops stretched outside active regions and accompanied sprays or lateral filament ejections. H brightenings occurred where these loops intersected the chromosphere. Inferred excitation velocities along the loops ranged between 300 and 1200 km s-1. It is suggested that these loops outlined closed magnetic fields guiding slow mode shocks from flares and filament eruptions.  相似文献   

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We have observed 10 solar bursts during the thermal phase using the Haystack radio telescope at 22 GHz. We show that these high frequency flux observations, when compared with soft X-ray band fluxes, give useful information about the temperature profile in the flare loops. The microwave and X-ray band fluxes provide determinations of the maximum loop temperature, the total emission measure, and the index of the differential emission measure (q(T)/T = cT–1). The special case of an isothermal loop ( = ) has been considered previously by Thomas et al. (1985), and we confirm their diagnostic calculations for the GOES X-ray bands, but find that the flare loops we observed departed significantly from the isothermal regime. Our results ( = 1–3.5) imply that, during the late phases of flares, condensation cooling ( 3.5) competes with radiative cooling ( 1.5). Further, our results appear to be in good agreement with previous deductions from XUV rocket spectra ( 2–3).  相似文献   

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DOUBLE-LOOP CONFIGURATION OF SOLAR FLARES   总被引:2,自引:0,他引:2  
Hanaoka  Yoichiro 《Solar physics》1997,173(2):319-346
We analyzed several flares, which are presumed to be caused by interactions between an emerging loop and an overlying loop. We call such a basic combination of loops a double-loop configuration, and we reveal its topology on the basis of the microwave and soft X-ray observations of the flares and the magnetograms. In many cases, the magnetic field of the flare loops shows a bipolar + remote unipolar structure, rather than a quadrapole structure. The footpoints of two loops are distributed in three magnetic patches, and two of the footpoints of the loops, one from the emerging loop and the other from the overlying loop, are included in a single magnetic polarity patch. Therefore, the two loops form a three-legged structure, and the two loops are not anti-parallel as assumed in the traditional reconnection models. Typically, the emergence of a parasitic polarity near the major preceding-polarity region or the following one in an active region creates this configuration, but, in one of the analyzed flares, two active regions are involved in the configuration. Not only the flares, but various other active phenomena – microflares, thermal plasma flows like jets, and surges – occur in the same magnetic configuration. Hence, the interaction between two loops, which forms the three-legged structure, is an important source of the various types of activity.  相似文献   

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An essential part in the mechanics under study is taking into consideration the effect of motions of the Universe objects upon that of an individual one surrounded by them including those infinitely far from it. Only macro-objects of the Universe are meant here.
Zusammenfassung Ein wesentlicher Bestandteil der Mechanik unter unserer Betrachtung ist die Berechnung des Einflusses auf die Bewegung eines individuellen Objektes von Bewegungen der Universum Objekte die es umringen einschließlich jene Objekte, die unendlich entfernt sind. Nur Makroobjekte des Weltalles sind in der Absicht dabei.

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In a statistical analysis of Debrecen Photoheliographic Results sunspot area data we find that the logarithmic deviation (logD) of the area decay rate D from the parabolic mean decay law (derived in the first paper in this series) follows a Gaussian probability distribution. As a consequence, the actual decay rate D and the time-averaged decay rate are also characterized by approximately lognormal distributions, as found in an earlier work. The correlation time of (logD) is about 3 days. We find a significant physical anticorrelation between (logD) and the amount of plage magnetic flux of the same polarity in an annulus around the spot on Kitt Peak magnetograms. The anticorrelation is interpreted in terms of a generalization of the turbulent erosion model of sunspot decay to the case when the flux tube is embedded in a preexisting homogeneous plage field. The decay rate is found to depend inversely on the value of this plage field, the relation being very close to logarithmic, i.e., the plage field acts as multiplicative noise in the decay process. A Gaussian probability distribution of the field strength in the surrounding plage will then naturally lead to a lognormal distribution of the decay rates, as observed. It is thus suggested that, beside other multiplicative noise sources, the environmental effect of surrounding plage fields is a major factor in the origin of lognormally distributed large random deviations from the mean law in the sunspot decay rates.  相似文献   

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The general conception of the critical inclinations and eccentricities for theN-planet problem is introduced. The connection of this conception with the existence and stability of particular solutions is established. In the restricted circular problem of three bodies the existence of the critical inclinations is proved for any values of the ratio of semiaxes . The asymptotic behaviour of the critical inclinations as 1 is investigated.
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