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1.
. , , . , t>1010 ( z<105) .
In this paper we continue the work of Weymann, investigating the causes of distortion of the spectrum of the residual radiation from the Planck curve. We discuss the distortion to the spectrum, resulting from recombination of primeval plasma.We then derive an analytic expression for the distortion to the equilibrium spectrum due to Compton scattering by hot electrons. On the basis of the observational data we conclude that a period of the existence of neutral hydrogen is inescapable in the hot model of the universe. It is concluded that any injection of energy att>1010 sec (red shiftz<105) give the distortions of the equilibrium spectrum.
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2.
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.
. . . 1.
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3.
Since the average relation between the angular momentaP and the massesM of galaxies can be represented by a power lawPM , we can define a relative angular momentum =P/M (or a constant timeP/M ). For a random motion picture within protogalaxies, should follow a Maxwellian distribution and consequently the dispersion of log should be 0.210.For the reasonable range of ( to 2), the limited sample of galaxies with known dynamical parameters gives between and 1 times the Maxwellian value. For the plausible special case =2 the reciprocal of the maximum rotational velocityv m is already a measure of and the larger sample ofv m-values not only yields the Maxwellian but, moreover, shows the shape of the distribution.
PM , =constP/M . , (lg )=0.210. 7/42, . =2 v m- .
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4.
We report here on high angular resolution observations of solar noise storm sources at a frequency of 75 MHz. The data for the study were obtained at the Gauribidanur Radio Observatory (long.: 77°2612 E, lat.: 13°3612 N) about 100 km north of Bangalore, India, during the solar eclipse of 24 October 1995. Our main conclusion is that there are structures of angular size 2.5 arc min in the outer solar corona.  相似文献   

5.
Résumé Il est envisagé dans ce travail un cas particulier du problème des trois corps solides. On suppose qu'un des corps est passif, c'est-à-dire qu'il n'agit pas sur les deux autres. Chaque corps posséde la symétrie axiale, ainsi que la symétrie par rapport à plan, perpendiculaire à cet axe, Au moment initial les plans de la symétrie des corps coinsident avec le plan principal des coordonneés. Alors il est possible de choisir les conditions initiales de sorte que les centres de la symétrie resterons toujours dans le plan principal, chaque corps tournant uniformement autour son axe. Nous nommerons ce problème — le problème restreint plant. Le cas le plus simple est le problème plan circulire, quand le centre d'un des corps actif décrit orbite circulaire authour d'autre corps actif. Ce problème se reduit à l'étude du mouvement du centre d'inértie du corps passif dans le plan principal —plan d'orbite circulaire du corps actif. Nous trouvons les conditions d'existence pour les solutions particulières du ce problème et posons la question de la stabilité des points de libration correspondantes. D'une manière plus détaillée nous envisageons le cas, où toutes les forces actives sont définiérs une par loi unique.
, . , , , . . , , . . , , . , , . , , . . . , , .
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6.
The conclusions of the present paper broadly are: (a) The galactic concentration of doubles by comparing the distributions in galactic latitudes 0°<20° and >40° is nearly twice as large as the galactic concentration of stars in general. (b) The astrographic catalogues are not complete in the fainter magnitudes. (c) The large value of the ratioT:O k (observed to optical number of pairs) from Kreiken's formula shows that almost all stars in the group 0<d5 and quite a few in the other two groups, viz., 5<d10 and 10<d15 might be shown true binaries. Consequently, Aitken's working definition of a true binary should be extended if it were to include all true binaries. (d) The doubles are probably stars of Population I. (e) The logarithm to the base 10 of the cumulative counts can be represented by an empirical relationA+B(m–1.5)+C(m–1.5)2.Communication presented at the International Conference on Astrometric Binaries, held on 13–15 June, 1984, at the Remeis-Sternwarte Bamberg, Germany, to commemorate the 200th anniversary of the birth of Friedrich Wilhelm Bessel (1784–1846)  相似文献   

7.
A limiting case of the problem of three bodies (m 0,m 1,m 2) is considered. The distance between the bodiesm 0 andm 1 is assumed to be much less than that between their barycenter and the bodym 2 so that one may use Hill's approximation for the potential of interaction between the bodiesm 1 andm 2. In the absence of resonant relations the potential, double-averaged by the mean longitudes ofm 1 andm 2, describes the secular evolution of the orbits in the first approximation of the perturbation theory.As Harrington has shown, this problem is integrable. In the present paper a qualitative investigation of the evolution of the orbits and comparison with the analogous case in the restricted problem are carried out.The set of initial data is found, for which a collision between the bodiesm 0 andm 1 takes place.The region of the parameters of the problem is determined, for which plane retrograde motion is unstable.In a special example the results of approximate analysis are compared with those of numerical integration of the exact equations of the three body problem.
m 0,m 1,m 2. , m 0 m 1. m 2, m 1 m 2 m 1 m 2 . , . . , m 0 m 1. , . .
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A cross-correlation study for time-lags of ±5 yrs between eleven ground based ozone stations (1957–1985) for = 40°N–75° N and = 30° E-114° W and five volcanic emissivity indices has shown their close connection: significant correlations well above 90% were obtained. Intepretation of these positive/negative correlations () was based on the global wind circulation (aided also by a 2-D, 3-D representation between, , ), and the types of volcanic aerosols leading to heterogeneous chemical reactions with ozone.  相似文献   

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14.
Pulsar nebulae     
Several of the exotic supernova remnants are re-interpreted as pulsar-illuminated former windzones. The class of supernova remnants thus splits into (i) (the usual) shell remnants and (ii) pulsar nebulae in which a (fairly young) pulsar blows its relativistic wind into its low-density environs.  相似文献   

15.
, . () . , , , . ( ), , , . . (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   

16.
From 17 through 21 April 1967, an international study week was held in the Bilderberg near Arnhem, Netherlands, with the aim of obtaining an internationally acceptable model of the solar photosphere and low chromosphere. It was found that such a model, based on observed intensities and center-to-limb observations of the solar continuous spectrum, could indeed be established. This model, henceforth called the Bilderberg Continuum Atmosphere (BCA), is shown in Table I, which gives the temperature, gas and electron pressures, and other data as functions of the continuous optical depth at 5000 Å between 5000 = 10–7 and 25. The model is characterized by a flat temperature minimum of 4600 °K between 5000 10–2 to 10–4. The model is homogeneous, and in hydrostatic equilibrium. A hydrogen-helium ratio of 10 has been assumed.Much divergence remains in the interpretation of line-profile observations with regard to the establishment of a photospheric model (Section 4). It proved to be as yet impossible to obtain reliable information on the variation with depth of the following functions: temperature fluctuations, turbulence velocities, convective velocities, and vibrational velocity amplitudes (Section 5). Provisionally, it is assumed that macro = 2 km/sec and micro = 1 km/sec, isotropic and independent of depth.  相似文献   

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Skomorovsky  V.I.  Firstova  N.M.  Kashapova  L.K.  Kushtal  G.I.  Boulatov  A.V. 《Solar physics》2001,199(1):37-45
A new two-bandpass birefringent filter has been produced at ISTP, Irkutsk for the investigation of the fine structure of the chromosphere. One filter passband is centered on the Hei 10830 Å line, the second one is centered on H. The FWHM of the Hei 10830 Å passband is 0.46 Å and of the H passband is 0.3 Å. A large number of filtergrams were obtained with the filter at the Sayan observatory. At the same time, spectral observations with high spatial and spectral resolution were carried out by the large solar vacuum telescope at the Baikal Observatory. We selected 29 `dark point' spectra with sizes from 2 to 13, as well as `dark points' on the filtergrams. Comparison of spectrograms and filtergrams has shown a good agreement of their size and intensity in relation with the surrounding chromosphere as well as the absence of primary line-of-sight velocities in both observation types. From spectral observations, the depth of 10830 Å is over 30% for some `dark points', and the FWHM is more than 1 Å. Hei 10830 Å line profiles in `dark points' are more deep and wide than in quiet regions. The optical depth of the chromosphere in `dark points' is estimated. Comparison with the unperturbed chromosphere showed that `dark points' in Hei 10830 Å are more optically thin than the nearby chromosphere.  相似文献   

20.
The anomalously high number of craters with diameter less than 2.8 km, the igneous nature of rocks from the Apollo landing sites, and the possibility of outgassing magmas in the lunar crust, suggest that fluidization may be a viable mechanism for producing many of the smaller lunar craters, Fluidization craters were formed in the laboratory by blowing gas through various thicknesses of particulate material. Gas pressure, regolith thickness, and the duration of gas streaming were controlled over practical experimental limits and compared with the resultant crater morphology. Low to moderate fluidization pressures on coarsely crushed limestone (Mø = 0.40, So = =0.50) with low cohesion (ø - 43°) produced bowl shaped, basin shaped, and flat bottomed craters. Bowl shaped craters change into basin shaped and/or flat bottomed craters with long durations of gas streaming. Cone, funnel, and flat-funnel shaped craters are indicative of high fluidization pressures. Craters formed in finely crushed limestone (Mø - 1.55, So - 0.85) that is electrostatically charged by the streaming gas, are flat bottomed. Terraced craters develop from slumping during and after the discontinuation of gas flow. Central mounds inn terraced craters result from slumping into a confined space. In particulate material, fluidization craters have high circularity and axial symmetry, similar to those produced by impact. The use of an impact model and crater morphology (normal, flat bottomed, and concentric) for estimating lunar regolith depth is questioned because similar craters can be produced by fluidizationn processes in a thicker regolith.On leave at the Earth Physics Branch, Dept. of Energy, Mines and Resources, Ottawa, Canada.  相似文献   

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