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1.
The Comptonization-softening of very hard X-ray photons withEm 0 c 2 in the cold electron gas is discussed. The frequency diffusion equation for Comptonization of hard X-rays has been derived to the zero-temperature approximation. By use of this equation, and under the assumption of pair-annihilation origin of hard X-rays, we calculated the energy spectrum withE>80 keV, for Cyg X-1, which is in good fit with the observation. The high-energy edge 400 keV of the observed spectrum and the small bump in the range 100–200 keV also can be explained by this way.  相似文献   

2.
We adopt the iterative least-squares method of Schmee and Hahn (1979) and extend it to the multiple regression case to investigate the dependence of the X-ray luminositíesL x of quasars on their optical liminositiesL 0 and redshiftsz. The method has several advantages, one of which is that we do not need the strong assumption that the values of the optical-X-ray index 0x of the detected and nondetected quasars should fall into the same range. We have found that correlations of 0x and log(1+z) or the look back time (z) are shown, but these are not firmly established due to the uncertainty present in the regression parameter. On the other hand, it is impossible for 0x to be independent ofL 0. We have also shown thatL x is less than proportional toL 0.  相似文献   

3.
We prove existence and multiplicity of T-periodic solutions (for any given T) for the N-body problem in m (any m 2) where one of the bodies has mass equal to 1 and the others have masses 2,..., N , small. We find solutions such that the body of mass 1 moves close to x = 0 while the body of mass i moves close to one of the circular solutions of the two body problem of period T/k i, where ki is any odd number. No relation has to be satisfied by k 2,...,k N.  相似文献   

4.
Using the see-saw mechanism and estimation of the hypothetical mass of the electron neutrinom e we find the hypothetical mass of muon neutrinom µ and hypothetical mass of the tau neutrinom .  相似文献   

5.
We consider a large massM and two small massesm 1 andm 2 (m 1 m 2;m 1,m 2M). The orbit ofm 1 is initially circular and the motion ofm 2 hyperbolic with respect toM. The orbital elements of the small masses are strongly modified after a close, single encounter betweenm 1 andm 2.An approximative method, similar to the theory of stellar encounters, is used to determine the probabilities of collisions, hyperbolas, direct and retrograde ellipses, as well as the mean values of the semimajor axes and their root mean square deviation after the encounter.The results are close to those which are obtained if the massm 2 is negligibly small, (Mm 1m 2;m 2 0), as should be also expected on general grounds.  相似文献   

6.
Approximation formulas are found for and , wherex(t) satisfies ,x(0)=x 0,x(1)=x 1. The results are applied to an example of two-body motion.  相似文献   

7.
During two observation periods in 1984 and 1985 we monitored the faint optical counterparts of seven X-ray binaries with a CCD camera attached to the Cassegrain-focus of the 2.2 m telescope at Calar Alto, Spain. The observation periods were 1984, September 25–27, and 1985, August 8–15.The transient sources 4U0042+32 and 4U0115+63 showed no active state.The search for an optical candidate of 4U0142+62 did not reveal any objectm v 24 within the EXOSAT error box.Within the EXOSAT error box of EXO2030+37 the reddest object was found to be very faint in blue in contrast to the blue Palomar plate.The analysis of the other three observed sources 4U1837+04, 1H1929+509, and 4U2129+47 is not yet finalized, but no unexpected bright or faint state of the sources has been found, 4U2129+47 is still in its present low state (m v =18), lasting at least since 1983.Paper presented at the IAU Colloquium No. 93 on Cataclysmic Variables. Recent Multi-Frequency Observations and Theoretical Developments, held at Dr. Remeis-Sternwarte Bamberg, F.R.G., 16–19 June, 1986.  相似文献   

8.
We consider the symmetric planar (3 + 1)-body problem with finite masses m 1 = m 2 = 1, m 3 = µ and one small mass m 4 = . We count the number of central configurations of the restricted case = 0, where the finite masses remain in an equilateral triangle configuration, by means of the bifurcation diagram with as the parameter. The diagram shows a folding bifurcation at a value consistent with that found numerically by Meyer [9] and it is shown that for small > 0 the bifurcation diagram persists, thus leading to an exact count of central configurations and a folding bifurcation for small m 4 > 0.  相似文献   

9.
The exact geometry of the Roche curvilinear coordinates (, , ) in which corresponds to the zero-velocity surfaces is investigated numerically in the plane, as well as in the spatial, case for various values of the mass-ratio between the two point-masses (m 1,m 2) constituting a binary system.The geometry of zero-velocity surfaces specified by -values at the Lagrangian points are first discussed by taking their intersections with various planes parallel to thexy-, xz- andyz-planes. The intersection of the zero-velocity surface specified by the -value at the Lagrangian equilateral-triangle pointsL 4,5 with the planex=1/2 discloses two invariable curves passing through the pointsL 4,5 and situated symmetrically with respect to thexy-plane whose form is independent of the mass-ratio.The geometry of the remaining two coordinates (, ) orthogonal to the zero-velocity surfaces is investigated in thexy- andxz-planes from extensive numerical integrations of differential equations generated from the orthogonality relations among the coordinates. The curves (x, y)=constant in thexy-plane are found to be separated into three families by definite envelopes acting as boundaries whose forms depend upon the mass-ratio only: the inner -constant curves associated with the masspointm 1, the inner -constant curves associated with the mass-pointm 2 and the outer -constant curves. All the -constant curves in thexy-plane coalesce at either of the Lagrangian equilateraltriangle pointsL 4,5, except for a limiting case coincident with thex-axis. The curves (x, z)=constant in thexz-plane are also separated by definite envelopes depending upon the mass-ratio into different families: the inner -constant curves associated with the mass-pointm 1, the inner -constant curves associated with the mass-pointm 2 and the outer -constant curves on both sides out of the envelopes. For larger values ofz, the curves =constant tend asymptotically to the line perpendicular to thex-axis and passing through the centre of mass of the system, except for a limiting case coincident with thex-axis. The geometrical aspects of the envelopes for the curves (x, y)=constant in thexy-plane and the curves (x, z)=constant in thexz-plane are also discussed independently.In the three-dimensional space, the Roche coordinates can be conveniently defined in such a way as to correspond to the polar coordinates in the immediate neighbourhood of the origin, and to the cylindrical coordinates at great distances. From numerical integrations of simultaneous differential equations generating spatial curves orthogonal to the zero-velocity surfaces, the surfaces (x, y, z)=constant and the surfaces (x, y, z)=constant are constructed as groups of such spatial curves with common values of some parameters specifying the respective surfaces.On leave of absence from the University of Tokyo as an Honorary Fellow of the Victoria University of Manchester.  相似文献   

10.
We study a theory for the ninth satellite of Saturn, Phoebe, based on the literal solution we have obtained in the main problem of the lunar theory.These series were computed by solving, by successive approximations, the Lagrange's equations expressed in variables, functions of the elliptic elements.We may consider the case of Phoebe simpler than a lunar case because we seek less precision (1/10 geocentric) than in the Lunar case, although the eccentricity of Phoebe is stronger.Main problem: our series are computed to the complete seventh order and a great part of the perturbations of the eighth and ninth order, where we have attributed to the small lunar parameters the order 1 tom 0=n/n 0,e 0,e, sin (i 0/2), the order 2 to 0=(a 0/a)((M 1–)/(M 1+M)) and the order 4 toµ 0(a 0/a)M 1 M/M 1 2 –M 2.In the case of Phoebe,µ 0 equal zero and ±0 is the ratioa 0/a.We study the further development of these series by using, instead of parameterm 0, the quantity m 0=n/n 0–m 1 wherem 1 is an approached value ofm 0, in order to accelerate the convergence of the series with respect tom 0.Comparison with a numerical integration we are adjusting a numerical integration to the observations. We have already more than 100 observations, for the period 1900–1957.At first, we compare the series of the main problem to a numerical integration of the Keplerian problem.

Proceedings of the Conference on Analytical Methods and Ephemerides: Theory and Observations of the Moon and Planets. Facultés universitaires Notre Dame de la Paix. Namur, Belgium, 28–31 July, 1980.  相似文献   

11.
In this paper, accretion disc and synchrotron emission models have been used to analyse simultaneous IR-optical-UV data of the BL Lac object 1727+502. In the following, some of its properties have been discussed. It is shown that the temperature of the disc is about 19, 000°k, the mass of the central black hole isM 8 5.4, and the accretion ratio is 10–3 M /yr.  相似文献   

12.
We consider the dynamics of a test particle co-orbital with a satellite of mass m s which revolves around a planet of mass M 0 m s with a mean motion n s and semi-major axis a s. We study the long term evolution of the particle motion under slow variations of (1) the mass of the primary, M 0, (2) the mass of the satellite, m s and (3) the specific angular momentum of the satellite J s. The particle is not restricted to small harmonic oscillations near L 4 or L 5, and may have any libration amplitude on tadpole or horseshoe orbits. In a first step, no torque is applied to the particle, so that its motion is described by a Hamiltonian with slowly varying parameters. We show that the torque applied to the satellite, as measured by s = js/(n s J s) induces an distortion of the phase space which is entirely described by an asymmetry coefficient = s/, where = m s/M. The adiabatic invariance of action implies furthermore that the long term evolution of the particle co-orbital motion depends only on the variation of m s a s with time. Applying a constant torque to the particle, as measured by s = js/(n s J p) is then merely equivalent to replacing = s/ by = (s – p)/. However, if the torque acting on the particle exhibits a radial gradient, then the action is no more conserved and the evolution of the particle orbit is no more controlled by m s a s only. We show that even mild torque gradients can dominate the orbital evolution of the particle, and eventually decide whether the latter will be pulled towards the stable equilibrium points L 4 or L 5, or driven away from them. Finally, we show that when the co-orbital bodies are two satellites with comparable masses m 1 and m 2, we can reduce the problem to that of a test particle co-orbital with a satellite of mass m 1 + m 2. This new problem has then parameters varying at rates which are combinations, with appropriate coefficients, of the changes suffered by each satellite.  相似文献   

13.
The usefulness of the classical Geometrical Optics and Diffraction (GOD) has been illustrated for scattering of electromagnetic radiation by very large dielectric and absorbing spheres. Various scattering parameters such as extinction efficiency, asymmetry parameter, radiation pressure, etc., have been calculated on the basis of GOD and compared with the equivalent results obtained as per the Mie theory. The spheres are assumed to be composed of pure and impure silicate-like or polystyrene material in the visual wavelengths. The representative indices of refractionm=m–im are chosen to bem=1.6 andm=0.00, 0.05, 0.10, 0.30, 1.00, 2.00, and 4.00. It is shown that the asymptotic values of a given scattering parameter obtained from the Mie theory calculations agree reasonably well with the corresponding result based on GOD. It is thus possible to estimate the minimum value (x min) of the size-to-wavelength parameterx(=2a/;a, the radius of the sphere; and , the wavelength of the incident radiation), such that, forx>x min, GOD holds good for certain specified accuracy.  相似文献   

14.
The aim of the present paper will be to present a new approach to the light changes of eclipsing binary systems. The light changes have been expanded into the Fourier-Bessel and Dini series. The coefficients of these expansions which are the Hankel transforms of the order of the loss of light (1–l) have been expressed in terms of the eclipse elements. These discrete Hankel transformsH (j m ) andH ( m ) valid for only the positive real zerosj m and m of the functionsJ and [xJ(x)+J (x)] have been generalized for any positive value of andy. Thus, these general expressions for the Hankel transforms of the light curves which are valid for all types of eclipses, for any arbitrary degree of the adopted limb-darkening law and, moreover, for any positive value of the free parameters andy, may be used for the solution of the elements of eclipsing binary systems.  相似文献   

15.
Evolution of a binary system with masses of 5m and 4m , respectively, and with orbital period of 1.41 days is studied by means of non-stationary model calculations under assumptions of conservation of total mass and total orbital angular momentum of the system. As a result of mass exchange between the components we obtain a binary with masses of 8.46 and 0.54m . Physical parameters of the final product indicate possible connection with shell stars.It is also pointed out that the new secondary component can become rotationally unstable soon after the end of mass exchange.  相似文献   

16.
The number of equivalence classes of central configurations (abbr. c.c.) in the planar 4-body problem with three arbitrary and a fourth small mass is investigated. These c.c. are derived according to their generic origin in the 3-body problem. It is shown that each 3-body collinear c.c. generates exactly 2 non-collinear c.c. (besides 4 collinear ones) of 4 bodies with smallm 40; and that any 3-body equilateral triangle c.c. generates exactly 8 or 9 or 10 (depending onm 1,m 2,m 3) planar 4-body c.c. withm 4=0. Further, every one of these c.c. can be continued uniquely to sufficiently smallm 4>0 except when there are just 9; then exactly one of them is degenerate, and we conjecture that it is not continuable tom 4>0.Paper presented at the 1981 Oberwolfach Conference on Mathematical Methods in Celestial Mechanics.  相似文献   

17.
Results from wind ionization calculations are presented which show how the P-Cygni profiles of superionized species such as O VI can provide information about the X-ray source characteristics of early-type stars. Using detailed radiative and atomic physics models, we find that a significant source of X-ray emission from Pup (O4 If) comes from a region in the wind located within roughly 1 to 2 stellar radii of the photosphere. Our results suggest that X-rays sources in which emission occurs exclusively at large radii (r a fewR * ) are inconsistent with UV P-Cygni profiles for O VI. Instead, we find that X-ray emission from shocks distributed throughout the lower regions of the wind (r 1 – 2R * ) is consistent with both X-ray and UV data, as well as mass loss rates deduced from radio andH observations.  相似文献   

18.
A new kind of restricted 3-body problem is considered. One body,m 1, is a rigid spherical shell filled with an homogeneous incompressible fluid of density 1. The second one,m 2, is a mass point outside the shell andm 3 a small solid sphere of density 3 supposed movinginside the shell and subjected to the attraction ofm 2 and the buoyancy force due to the fluid 1. There exists a solution withm 3 at the center of the shell whilem 2 describes a Keplerian orbit around it. The linear stability of this configuration is studied assuming the mass ofm 3 to beinfinitesimal. Explicitly two cases are considered. In the first case, the orbit ofm 2 aroundm 1 is circular. In the second case, this orbit is elliptic but the shell is empty (i.e. no fluid inside it) or the densities 1 and 3 are equal. In each case, the domain of stability is investigated for the whole range of the parameters characterizing the problem.  相似文献   

19.
Simultaneous observations of hard X-ray and optical emission from Sco X-1 were carried out at Hyderabad, India, on April 16 and 19, 1972. During the first and the second observations Sco X-1 was on the average in a bright phase ofB=12.5 mag. and a slightly darker phase ofB=12.7 mag. respectively. During the first observation the X-ray intensity in the energy range 20–40 keV measured with balloon borne scintillation counters showed an enhancement of a factor of about two in coincidence with an optical flare ofB0.2 mag., whereas the apparent temperature derived from the X-ray spectrum observed in the energy range 20–35 keV showed no appreciable change. Both the X-ray intensity and the apparent temperature observed on April 19 are considerably lower than those observed on April 16. Taking into account the effect of radiative transfer in a hot plasma, the electron density and the optical depth for electron scattering of the plasma cloud are derived asn e 3×1016 cm–3 and es 10 for the quiescent bright phase. The flare is explained by an increase of the plasma mass by about 30% and an increase of es by es 1 without appreciable change of the plasma temperature. The results on April 19 is interpreted as indicating that the quiescent dark phase may be characterized by a decrease of the plasma mass, its contraction and lower temperature.  相似文献   

20.
The effect of X-ray irradiation on the line-driven stellar wind in X-ray binary systems is studied. The product of the X-ray luminosityL x and the densityn in the wind is a measure to distinguish between the optically thin and thick wind regimes. For an X-ray source of the radiation temperature of 10 keV, the critical value(L x n) c , is of the order of 1037 erg s–1 cm–3; hence, most of wind-fed X-ray sources lie in the optically thick wind regime because ofL x n>(L x n) c . Then the wind structure is determined not only by the parameter =(L x /nR 2),R the distance from the X-ray source, but also by the optical thickness due to helium. The formation of fully ionized helium region depends onL x andn in a way different from that of the Strömgren sphere. In such an optically thick wind, the region behind the He II ionization boundary is little affected by X-ray irradiation and the trace elements remain to be responsible for wind acceleration. Thus, its location is important for the structure of the wind and the interpretation of various phenomena in objects such as wind-fed X-ray pulsars.  相似文献   

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