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1.
视超光速运动的相对论超光速模型   总被引:3,自引:0,他引:3  
从相对论出发,在视超光速源质心相对于观测静止的条件下,推导出两个向相反方向运动的视超光速子源之间的视速度方程,这一方程包含了相对论射束模型的表观横向速度公式,且对高,低速不同条件均为适用。  相似文献   

2.
视超光速源的统计分析   总被引:2,自引:0,他引:2  
洪晓瑜  蒋栋荣 《天文学报》1995,36(2):147-158
本文收集了视超光速源样本的有关观测数据,在同步加速自康普顿散射机制下导出了各源的多普勒因子,再利用视超光速源的相对论射束模型计算样本源的有关物理量,如射电光度和亮温度,并与它们的观测值作直接的比较,得到较好的相关结果。这些结果支持了活动星系核中具有相对论射束运动的假设。同时我们比较了样本源的射电、光学、X射线的发现它们之间有一定的相关性,说明在不同波段上的辐射机制可能存在某种联系。  相似文献   

3.
覃一平  樊军辉 《天文学报》1997,38(2):156-159
本文利用文川提供的视超光速运动数据,对标准宇宙模型、相对论束模型及同步加速自康普顿散射机制在视超光速运动计算方面是否相容的问题进行统计检验.结果表明,理论预言与实际数据相吻合,上述诸理论是相容的,并且它们对视超光速运动的综合解释是合理的.  相似文献   

4.
本文利用新的相对论理论模型研究了视超光速源3C345中节点C4的内禀变化。  相似文献   

5.
于秦生 《天文学报》2001,42(2):148-154
在源的质心固定的视超光速模型的基础上,进一步出在质心运动情况下的视超光速运动的视速度议程,在喷流方向与源的退行方面相反的情况下,推导核与子源速率相等及核固定条件下子源真实速度的方程,然后代入视速度和由自康顿效应推算的喷流与视线的夹角数据,从而求出上述极值条件下子源的真实速度,再与对应源的哈勃红移速度相对照,结果发现,源的运动对其子源的速度没有影响。  相似文献   

6.
用相对论加速喷流模型对48个具有视超光速的射电源进行了分析,结果不但支持流行的喷流模型而且说明加速模型是合理的。  相似文献   

7.
视超光速运动与加速模型   总被引:1,自引:1,他引:0  
用相对论加速喷流模型对48个具有视超光速的射电源进行了分析,结果不但支持流行的喷流模型而且说明加速模型是合理的。  相似文献   

8.
本文从简要总结迄今所发现的视超光速源开始。介绍近年来探测到的视超光速源之一——类星体3C 454.3的VLBI多频段,多历元观测及其主要结果。采用列表对比方式表明此源相对其他视超光速源的一般特征呈现的特殊性。最后对此特殊的视超光速源的可能解释作初步讨论。 本文可以看作是对3C453.3观测已有报导[12]和[13]的进一步补充。  相似文献   

9.
艾小白 《天文学进展》2001,19(2):179-183
论述量子远程通讯的最新成就很可能意味着自然界存在超光速的信息联系,狭义相对论又面临新的考验,若考虑虚数“i”的作用,狭义相对论可与物质的超光速运动相容,而且不违反因果律,即使自然界存在超光速的物质运行也不可能动摇狭义相对论,建议设计实验测量德布罗意波的相速度并深入研究波粒二象性。  相似文献   

10.
作为上一篇文章的继续,本文从总结迄今已探测到的视超光速源的一般特征出发,简要地讨论了视超光速源在活动星系核分类研究中的地位;并综述了较普遍接受的对于视超光速源的一些理论探讨。文章的最后简述了目前对视超光速源观测的问题和前景。  相似文献   

11.
Based on the relativistic model of the apparent superluminal motion and under the condition that the center of mass of a superluminal radio source remains in motion relative to the observer, the equation of the apparent velocity between nucleus and component is derived. Assuming that the directions of jet and movement of superluminal radio source are opposite, then, supposing that the velocities of nucleus and components of SLS are equal and the nucleus is fixed, the equations of real velocity are respectively derived. With the data of Vapp and θ substituted in the equation of real velocity, the velocity of the components of SLS is obtained. Comparing the real velocity with the velocity of Hubble redshift of SLS, it is concluded that the movement of SLS has no influence on the velocity of components.  相似文献   

12.
Superluminal Motion and Polarization in Blazars   总被引:3,自引:0,他引:3  
A relativistic beaming model has been successfully used to explain the observed properties of active galactic nuclei (AGNs). In this model there are two emission components, a boosted one and an unbeamed one, shown up in the radio band as the core and lobe components. The luminosity ratio of the core to the lobe is denned as the core-dominance parameter (R = LCore/LLobe). The de-beamed radio luminosity (Ldbjet) in the jet is assumed to be proportional to the unbeamedluminosity (Lub) in the co-moving frame, i.e., f = Ldbjet/Lub, and f is determined in ourprevious paper. We further discuss the relationship between BL Lacertae objects (BLs) and flat spectrum radio quasars (FSRQs), which are subclasses of blazars with different degrees of polarization, using the calculated values of the ratio f for a sample of superluminal blazars. We found 1) that the BLs show smaller averaged Doppler factors and Lorentz factors, larger viewing angles and higher core-dominance parameters than do the FSRQs, and 2) that in th  相似文献   

13.
Starting from the theory of gravitation in flat space-time of Petry (1981), the gravitational field of a static spherically-symmetric body is studied. Petry (1982) has shown that this field in the exterior of the body depends on a parameter which is fixed by the interior solution, i.e., it depends on the density of matter, the pressure, the equation of state, etc. If this parameter is small, the results for the well-known effects, i.e., redshift, deflection of light, perihelion shift, and radar time-delay, agree with those of general relativity. In this paper, we study these effects for larger values of this parameter. Furthermore, for sufficiently large positive values of the parameter, in the neighbourhood of the body the radial velocity of light can exceed several times the vacuum light-velocity. Therefore, the components of such an object can move away with velocities a few times greater than that of light in agreement with the observed superluminal velocities in extragalactic objects.  相似文献   

14.
We have collected an up-to-date sample of 123 superluminal sources (84 quasars, 27 BL Lac objects and 12 galaxies) and calculated the apparent velocities (βapp) for 224 components in the sources with the A-CDM model. We checked the relationships between their proper motions, redshifts,βapp and 5 GHz flux densities. Our analysis shows that the radio emission is strongly boosted by the Doppler effect. The superluminal motion and the relativistic beaming boosting effect are, to some extent, the same in active galactic nuclei.  相似文献   

15.
Neutrino objects can cause the apparent superluminal separation in quasars as gravitational lenses. In this paper we analyse this possibility and calculate the differential bending for different equilibrium configurations of neutrino objects.  相似文献   

16.
In the relativistic case, the dispersion equation of longitudinal oscillations in unmagnetized, collisionless and isotropic plasmas of fast electron distribution is derived from the longitudinal dielectric constant of plasma. The equation is analytically solved, and the long-wavelength and short-wavelength dispersion relations are obtained. Because of the discontinuity of the analytical dispersion curve, the dimensionless dispersion equation of longitudinal oscillations is numerically calculated to obtain the full dispersion curve of longitudinal oscillations in relativistic plasmas of fast electron distribution. Further more, by fitting the numerical solution, a simple functional expression of the dispersion curve is given in favor of applications. Finally, in the extremely relativistic case, the dispersion relation of fast electron distribution is compared with that of Maxwell distribution. It is shown that the two kinds of dispersion relations have similar properties in a certain range of wave numbers.  相似文献   

17.
We present extensive multi-epoch VLBI observations of the quasar 3C 380 which reveal a bent parsec-scale radio jet with complex substructure which exhibits superluminal motion out to ∼100 pc from the active core. The general characteristics of the jet and its motion are similar to those in several other well-studied superluminal sources, most notably a rapid increase in the opening angle at a projected distance of a few tens of parsecs from the core and apparent acceleration along the jet. This acceleration could be a simple kinematic effect associated with bulk flow at a constant speed, but at a varying angle to the line of sight. The jet is well resolved in the transverse direction for the majority of its length and resembles numerical simulations of a jet disrupted by the rapid growth of sinusoidal 'Kelvin–Helmholtz' modes. Our maps also reveal extremely rapid localized variations in brightness which have not yet been seen in other nuclear jets. We suggest that phase effects, arising from the intersection of oblique shocks, may be the cause of these dramatic changes. 3C 380 is often classified as a compact steep spectrum (CSS) source; however, in contrast to the majority of CSS sources, it is likely that 3C 380 is simply a powerful FRII source seen approximately end-on.  相似文献   

18.
The gravitational radiation of n = 1 polytropes undergoing quasiradial pulsations is examined. The intensity of the gravitational radiation and the gravitational wave amplitudes are calculated for polytropic models of white dwarfs and neutron stars when the energy of rotation of the object serves as the source of the radiated energy. Calculations of h0 show that objects with a polytropic equation of state can describe the expected gravitational radiation from white dwarfs and neutron stars. The gravitational radiation of polytropic models of galactic nuclei and quasars is also examined. These objects can create a high enough background of gravitational radiation at frequencies of 10-8–10-11 Hz for gravitational wave detectors operating in this frequency range. __________ Translated from Astrofizika, Vol. 48, No. 4, pp. 603–612 (November 2005).  相似文献   

19.
The inclusion of non-canonical perturbations in symplectic integration schemes has been discussed. A rigorous derivation of an analog for theWisdom–Holman (1991) method, such that velocity dependent forces can be included, has been outlined. This is done both by using the δfunction formalism and also by means of formal Hamiltonization. Application to the relativistic corrections in Solar System integrations is discussed as an example. Numerical experiments confirm the usefulness of the method. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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