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1.
This is a first attempt to find a realistic explanation of the observed redshifts of quasars associated with galaxies, by considering, in addition to the inertial, also the gravitational time dilation in the strong field of quasars interpreted as huge black holes accreting matter from their surroundings. This interpretation allows us to understand the observed predominance of excess redshifts of quasars and construct possible semiquantitative models for the pair NGC 4319/Markarian 205. The proposed models do not contradict to the present astrophysical knowledge, but a selection of the most satisfactory one is still difficult because of the existing uncertainty in estimates of the sizes of radiating regions in matter accreted by a flying black hole.Essay received 2 March, 1979 by the Gravity Research Foundation (Gloucester, Mass., U.S.A.) and selected for Honorable Mention for 1979.  相似文献   

2.
Explosions of quasars and young galaxies at large redshifts must cause propagation of blast waves in the metagalactic medium. The shock waves formed can, during the radiative cooling stage, produce dense cold spherical shells around the epicentres of explosions. But, even before that, at the stage of adiabatic expansion, each spherical shock-wave front, if it lies on one line-of-sight with a more distant quasar, can imprint into the quasar spectrum a specific absorption doublet with a distance between the components (in the rest frame) 0 3 Å. The L doublet components have a small but the same equivalent widthW 0 0.3 Å, the ratioW 0/0 weakly depending onW 0 ifW 0 is small. We demonstrate here that such absorption L doublets are really present among the L forest in the absorption spectra of distant quasars which are, according to Sargentet al. (1980), of mostly intervening (and not intrinsic) origin. Further accumulation of data on absorption doublets, which can serve as direct indicators of metagalactic shock-waves, may provide valuable information about the physical conditions in the metagalactic gas at large redshifts.  相似文献   

3.
With the aid of a simple black hole model of quasars we have found that the majority of the distinguishable emission lines in the spectrum of the quasar 1604+179 can be assigned to two redshift systems,z r =3.712 andz b =2.701. The appearance of double emission redshifts means that this quasar might be a massive black hole (of mass 108 M M1011 M ) with a ring-like emission line region (of radius 1 light-day r 01 light-year) in its accretion disk.  相似文献   

4.
It is argued that accreting supermassive black holes ejected from centers of galaxies are the likely models for the quasars observed in association with galaxies. Also pointed out are the implications of a recent suggestion by Horák (1982) to account for the excess redshifts of such quasars due to a combined effect of peculiar Doppler-motion and the gravitational field.  相似文献   

5.
The gravitational radiation from a highly relativistic test particle spiralling inward toward a Kerr black hole along a conical surface is estimated. The spectra of several lowest multipoles depending on the polar angle of the falling particle at infinity are obtained for the frequency band c 3 GM–1.  相似文献   

6.
The angular size-redshift test for quasars was compared with various cosmological models including non standard models. The possible effects of radio source orientation and relativistic beaming were taken into account in the analysis.It was found that orientation effects alone were not sufficient to explain the observed-z relation in terms of Friedmann models. In addition, linear size evolution of the formD ~ (1 +z)n , with 0.75 n 1.2 would be required for 0 1.0, or possibly an inverse correlation between luminosity and linear size. The non-standard cosmological models all gave better fits to the deprojected data than the Friedmann models in the absence of evolutionary effects, with the tired light effect providing the best fit.  相似文献   

7.
We present simple two-layer models of Uranus with rocky core and polytropic envelope satisfying exactly the observed mass, radius and the gravitational moments. The models show that the value of the fourth order zonal harmonic isJ 4 –38×10–6, whileJ 6 10–6. More elaborate threelayer models fail to satisfy the observational constraints of the ice/rock ratio and/or of the rotation period. We conclude that three-layer models with uniform chemical composition in each layer may be too restrictive. More realistic models should account for variable chemical composition within each layer.  相似文献   

8.
In dense interstellar clouds or in the surroundings of just-formed stars, the larger grains form proto-cores by segregating from the gas under the influence of the gravitational field of the cloud during intervals of the order 108 yr.If the mass of the proto-cores is smaller than a certain limit, the object possesses a negligible atmosphere and remains composed mainly of solid grain material. If the mass of the proto-core exceeds the limiting mass, the proto-core can bind around it an atmosphere. When the temperature of the opaque part of the atmosphere is only fractions of a degree above the temperature of the surrounding tenuous gas, gravitational contraction of the opaque part of the atmosphere sets in, forming gaseous objects up to stellar mass range.Binary and multiple systems originate from neighbouring proto-cores, through gravitational contraction of both their separate and common outer atmospheres.Pycnonuclear reactions are not able to prevent a star with mass 0.08M from cooling to the black dwarf stadium.  相似文献   

9.
In the bounds of the totally nonmetric model of gravitational interaction theory (gravidynamics) the strong field of a compact object (a collapsar) — an analogue to the black hole in general relativity — is investigated. In the case of utmost strong (for gravidynamics) collapsar, field a region filled, by matter (a bag) must have the radius equal tor *=GM/c 2 10 km at the total collapsar massM7M . Only half of the collapsar mass is contained in the bag, the other one of its total energy (Mc 2 ) is distributed in the space surrounding the bag in the form of a coat, i.e., in the form of continuous medium (a relativistic gas) of virtual gravitons. The object must have the surface (the bag surface) with absolutely definite physical properties. The potential of such a surface is finite (+=-c 2/2) and the particle mass finding itself in a bound state on the bag surface is two times less than the mass of the same particle in a totally free state. The bag surface can perform periodic oscillations (pulsations) with the periodGM/c 2 3×10–5 s. An energy density inside the bag with the utmost strong gravitational field or with an utmost dense coat shrouding the bag is determined by gravitation theory constants only and depends on the distance to the bag centerr in the following way: (r)=(c 5 /8G)r –2. The bag matter in the case is most probably in the state of quark-gluon plasma.  相似文献   

10.
The cooling wave apparently arises at some phases of the supernova expansion. A number of basic properties of the cooling wave are considered. The dependence of light curve and colour temperature on chemical composition and density distribution law has been investigated in detail. An estimation of total mass ejected by supernovae type II leads to the value of 20M . The necessity of further careful spectroscopic and photometric observations at prolonged postmaximum phases, especially for supernovae type II, is emphasized.  相似文献   

11.
Hong Wei Li 《Solar physics》1986,104(1):131-136
The variations of the growth rates of ECM at first four harmonics in X-, Z-, and O-modes excited by a hollow beam distribution of weakly relativistic electrons with a parameter p / e are presented in this paper. The results show that the second harmonic of ECM in X-mode dominates the instability if < 1, and if 1.2 , 2 or 2.2 3 the third or fourth harmonic will dominate. The second and third harmonics of Z-mode waves grow faster only if 2 2.2 and 3 3.2, respectively, so it would not be a competition in most cases. It is suggested that the ECM emission at these harmonics in X-mode is a possible mechanism to produce solar spike emissions with high brightness temperature at shorter and longer decimetric wavelengths.Proceedings of the Workshop on Radio Continua during Solar Flares, held at Duino (Trieste), Italy, 27–31 May, 1985.On leave from the Department of Astronomy, Nanjing University, Nanjing, The People's Republic of China.  相似文献   

12.
For the QSO 3C 273 we derive, on the basis of two different theoretical models, expressions for a lower limit to the mass of the QSO, as a function of its distance. We conclude that an appreciable gravitational redshift component is consistent with the observational data only if the QSO mass is at least Galactic in magnitude. The setting of an independent upper limit to the QSO massM1010 M could indicate that the QSO redshift is predominantly cosmological in nature.  相似文献   

13.
A two-stage model of the propagation of 1–50 MeV solar-flare cosmic rays is presented. The first stage consists of a thin spherical shell of radius r a near the Sun which feeds particles into interplanetary space (the second stage) where they propagate along the Archimedean mean interplanetary magnetic field under the influences of anisotropic diffusion, convection, and energy changes. To calculate the time dependence at a fixed point in space, account is taken of the corotation of flux tubes past the observer.It is shown that the well-known east-west effect of the time-to-maximum cannot be obtained if the injection from the first stage is impulsive and thus a time and longitude dependent release for the second stage is essential. This is achieved by treating the first stage as a thin, spherical, diffusing shell of radius r a with diffusion coefficient s, from which particles leak into interplanetary space at a rate determined by the leakage coefficient .With this model we are able to reproduce simultaneously four principal features of solar events observed at r = 1 AU: (i) the east-west effect, i.e. the time-to-maximum as a function of flare longitude; (ii) the three phases of the anisotropy vector variation; (iii) the time-to-convective-phase as a function of flare longitude; and (iv) the longitudinal distribution of the differential intensity. Our best estimates of the parameters of the near-Sun propagation are that 0.01 hr–1 s/r a 2 0.02 hr–1 and 1/15 hr–1 1/10 hr–1. For the interplanetary propagation we estimate /V - 1.2AU with , the effective cosmic-ray diffusion coefficient and V, the solar-wind speed.  相似文献   

14.
I give an interpretation of a result of Simpsonet al. (1988) on the variation with kinetic energyT i of the mean pathlengthX m (T i ) of the galactic cosmic rays (CGRs) in the range 0.1T i 10.0 GeV nucl–1. I argue that the data onX m (T i ) may be interpreted in terms of a model of GCR diffusion on the one-dimensional Alfvén-wave turbulence, having a cutoff in the spectrum at frequencies h , where h is the proton gyrofrequency. The cutoff results in changing of the character of variation of the GCR diffusion coefficientD(T i )T a in the rangeT i 1 GeV nucl–1 towards some more complicated variation at 0.1T i 1.0 GeV nucl–1 due to the peculiarities of the pitch-angle scattering at 900.  相似文献   

15.
By use of a theoretical scheme presented in a previous publication it is possible to calculate the functional relations among the actual cosmological redshift, the peculiar velocity, and the change of the angular separation for quasar-galaxy pairs. Applying the results to the quasi-stellar object Markarian 205 which seems to be connected with the spiral galaxy NGC 4319 we find, under the assumption of two different limiting cases, that the distance of the object Markarian 205 is reduced drastically, and that the velocity of one or the two objects remains under 0.1 of the velocity of light if the angle δ between the direction of motion of the quasar and the Earth quasar-galaxy line lies in the range 120°?δ?180°.  相似文献   

16.
The effect of southward or northward changes in the interplanetary magnetic field is examined statistically in the nightside magnetosphere over the range of 6.6 to 80R E from the Earth. After southward changes, the deformation of the magnetosphere toward a greater antisunward extension of field lines occurs at 6.6R E with 10 min delay and spreads down the tail to 80R E in 30 min. Around the onset of the field-line collapse that occurs 1–2 hr later, the southwarddirected field is observed briefly in the distant tail. The effect of northward changes could not be recognized in the lobe region of the tail.  相似文献   

17.
If the photon were to have a rest mass near the best present upper limit,m3×10–53 g, Maxwell's equations would be inapplicable over distances exceeding about 1015 cm, with profound implications for cosmic electrodynamics. This paper deals with electrodynamic and gravitational effects of the non-Maxwellian stresses which would be associated with large-scale magnetic fields in quasi-static plasmas in these circumstances. The existence of moderately dense interstellar gas clouds with relatively strong magnetization shows thatm10–58 g. General relativity must be used to calculate even the Newtonian gravitational effects of electromagnetic fields, and it is shown here that the Newtonian potential caused by the non-Maxwellian stresses just cancels that caused by the non-Maxwellian energy density. Previous arguments based on the latter alone are therefore invalid.  相似文献   

18.
Dust grains of radiir g 3×10–6 cm, injected into the intercloud medium at speeds in the range 107–108 cm s–1, may be stochastically accelerated to speeds 0.1c due to scattering by irregularities in the galactic magnetic field.  相似文献   

19.
One-armedglobal oscillations in a non-selfgravitating polytropic disk rotating around a star are investigated. The unperturbed disk is axisymmetric, geometrically thin, and extends infinitely in the radial direction keeping its thickness constant. Perturbations considered are inviscid and adiabatic. It is found that there are one-armed retrograde wave modes which are trapped in an inner region of the disk. The eignefrequency of the lowest order mode is given by K(r s)(z 0/r s)2, wherer s is the radius of the central star,z 0 is the half-thickness of the disk, and K(r s) is the Keplerian angular frequency at the surface of the star.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984.  相似文献   

20.
An approximate analytical method of solving the polytropic equilibrium equations, first developed by Seidov and Kuzakhmedov (1978), has been extended and generalized to equilibrium configurations of axisymmetric systems in rigid rotation, with polytropic index,n =n p + n , nearn p =0, 1, and 5. Though the details of the method depend on the value ofn p , acceptable results are obtained for | n | 0.5 to describe slowly rotating configurations in the range 0n1.5, 4.5n5. In the limit of rotational equilibrium configurations, when the distorsion may be large enough, a satisfactory approximation holds only in the range 0n, 1n1.5, 4.5n5.  相似文献   

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