视超光速源的统计分析

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。     

On the existence of transverse relativistic aberrations in moving mirror

Relativistic aberration and Doppler effects on rotating mirrors have been claimed (Ragazzoni & Claudi, 1995) and later refuted (Hickson, Bhatia & Iovino, 1995). While an experimental confirmation of the absence of the Doppler effect has been carried out in 1974, a measurement of the absence of the aberration effect is missing. It is shown that analyzing published data on the LAGEOS pulse-return signature an experimental confirmation of the absence of the effect is obtained.     

Hamilton's principle and the vorticity laws for a relativistic perfect fluid

Abstract

The equations for a relativistic perfect fluid result from the requirement that the total mass-energy be stationary with respect to variations δx^α(a, b, c, s) in the space-time location of the fluid particle identified by Lagrangian labels (a, b, c) at the point s on its world-line. By considering variations of the Lagrangian labels that leave the specific volume and entropy unchanged, we obtain a general covariant statement of vorticity conservation. The conservation laws for circulation, potential vorticity, and helicity are simple corollaries. This Noether-theorem derivation shows that the vorticity laws have no analogues in particle mechanics, where the corresponding particle labels cannot be continuously vaned.     

The model of a flat (Euclidean) expansive homogeneous and isotropic relativistic Universe in the light of the Wilkinson Microwave Anisotropy Probe (WMAP) observations

The Wilkinson Microwave Anisotropy Probe (WMAP) confirmed the model of a flat (Euclidean) expansive homogeneous and isotropic relativistic universe with the total zero mass (energy), which describes the properties of our observed expansive homogeneous and isotropic relativistic Universe in the first (linear, Newtonian or classical-mechanical) approximation.     

电提取离子法工作中的质量检查问题

电提取离子法在提取离子时是一个动态过程，提取量不但与提取时间有关，而且与指示电极的位置有关。检查工作量应布置在有电提取离子法异常的地段上，把质量检查和异常检查合并。第一、二次提取的异常明显存在，相对误差在20％以内，是矿致异常；第二次撮以量大于第一次几倍或更多，显示有隐伏金矿体存在；第二次提取量比第一次稍大，相对误差大于60％，提取量的数值小于或稍高于背景值，是背景区。2次测定结果的相对误差δ≤45％为合格，一个级。对四级质量的成果应扩大到20％的检查量，若质量仍达不到要求，应在检查量所代表的范围内返工。     

Elliptic-type motion in Fock's gravitational field

The elliptic-type motion in the gravitational field found by Fock as exact solution of Einstein's vacuum equations in the case of spherical symmetry (Solution called here Fock's gravitational field) is studied by means of a classic method based on the perturbation theory. Regarding the deviations of the orbit from a Kepleian orbit as perturbations, the first and second order variations of the Keplerian orbital elements over one nodal period as well as those of the nodal period itself are determined.     

Electromagnetic Field of a Cylinder with a Periodic Current: Energy Flux from a Relativistic Jet

An exact solution is obtained for the electromagnetic field surrounding an infinitely long, conducting cylinder with a periodic axial electric current. The solution simultaneously gives the field near the cylinder and in the transition to the wave zone. The flux of electromagnetic radiation emitted by the cylinder is calculated for oscillations with long wavelengths greatly exceeding the radius of the cylinder. This solution can be used to describe the electromagnetic field around narrowly collimated jets from active galactic nuclei and quasars.     

引力波、引力波源和引力波探测实验

引力波是爱因斯坦和其他物理学家提出的关于广义相对论的四大预言之一。除了PSR1 91 3 + 1 6引力辐射阻尼的观测提供了引力波存在的间接证据外 ,科学家至今仍没有在实验室中确证引力波的存在。由于人类目前的技术水平还不可能在实验室中产生强度可供探测的引力波 ,而宇宙中存在大量大质量、高速运动的天体 ,有可能产生较强的引力波 ,天体引力波源自然成为现阶段科学家研究引力波的首选。本文介绍广义相对论框架下预言的引力波性质 ,引力波探测的理论依据 ,共振型棒式天线和激光干涉仪两大类探测器的基本原理 ,引力波探测实验的现状和面临的困难 ,科学家采取的对策 ,以及爆发型和连续型两类天体引力波源。最后介绍了正在计划中的几个引力波探测空间实验     

Extragalactic sources with one-sided radio structure

A list has been compiled of 49 extragalactic sources, most of them identified with quasars, that appear to have a one-sided (D₂ type) radio structure characterized by a single outer component displaced from a compact central (nuclear) component coincident with the optical object. The observed properties of a subsample of 28 D₂ quasars that have an overall angular size larger than 5 arcsec are briefly discussed and compared with those of normal (D1 type) double quasars. It is found that the central components in most D₂ sources account for more than half the total flux density at high frequencies in contrast to the D₁ quasars which generally have less than 20 per cent of their total flux density in a central component. This makes it very unlikely that D₂ sources are just those D1s in which there is a large intrinsic difference in the flux densities or separations of the two outer components. The observed properties of D₂ sources are easier to understand in the relativistic beaming interpretation in which their axes are inclined at smaller angles with the line of sight compared to D₁ sources.     

相对论喷束模型中表现速度计算的修正

在相对论喷束模型中，假设源的核在观测者静止坐标系中不动的前提下，推出了现在已得到广泛承认和采用的计算相对论等离子团横向视速度的公式．随着观测精度的提高，对核固定不动的假设提出了怀疑，认为有必要重新估价表现横向速度公式的正确性，并在更普遍的框架下，找出该公式的修正形式．本文试图对几种根据目前对射电源一般结构认识提出的模型，初步探讨这种修正的可行性．