关于太阳场中存在着新以太场介质的天体运动方程

一、有介质阻尼作用的天体运动方程 在天体力学中，曲线运动的加速度为式中 ｒ０和 Ｐ０分别为径向和横向单位矢量．在平面极坐标系中，如果不考虑天体在运动中所受到的介质阻尼作用，有天体的运动方程 解方程组（Ⅰ），可求出天体的运动方程及万有引力 实际上在太阳系、银河系和河外星系内都存在着一个随引力场中心一起运动的新以太场介质．美国人Ｒ．Ａ．Ｍｕｌｌｅｒ对２．７Ｋ各向异性的宇宙背景微波辐射所作出的新以太介质的存在及其漂移的解释，由新以太漂移理论所计算出的地球绕太阳运动速度３０千米／秒、太阳绕银河中心运动速度大…     

宇宙射线跟随银河系的旋转

高能宇宙射线来自天空中某个特定的区域，并与银河系中我们所在的旋臂共同旋转．这些数据或许能够帮助我们理解我们的银河系如何与太阳磁场相互作用．     

恒星S2在银河系超大质量黑洞周围运动效应图

<正>此图展示了非常靠近银河系中心超大质量黑洞的恒星S2的轨迹。当它靠近黑洞时,很强的引力场会使恒星的颜色略微移向红色,这是爱因斯坦广义相对论的效应所致。此图中,为清晰起见,夸大了恒星的颜色和大小。     

估算太阳的寿命

估算太阳的寿命张海（上海先锋电机厂教育中心２０００７２）按照目前公认的大爆炸理论，１５０亿年前的一个特定时刻，在一个奇点上，炸出了一个宇宙──一个广漠无垠、神奇莫测的宇宙．在这个宇宙中，拥有上千亿个类似银河系的巨大星系，而在银河系中又拥有上千亿个类似...     

宇宙线的百年研究

二十年的大气电离之谜导致了宇宙线的发现．宇宙线的研究打开了粒子物理学的大门．而今天，宇宙线又为银河系外的天体物理学开启了一扇窗口．     

宇宙轻元素丰度研究的新进展

介绍了宇宙轻元素丰度的标准大爆炸核合成（ＳＢＢＮ）模型、理论和观测状况，特别是１９９４年的最新进展：已有三位有效数的４Ｈｅ丰度原初值Ｙｐ与由银河系观测推得的Ｄ＋３Ｈｅ丰度原初值ｙ２３ｐ间出现矛盾可能性，使ＳＢＢＮ模型面临考验；高红移吸收云中氘丰度测量的有关结果与原有２３显著矛盾，而与Ｙｐ偏小的趋向相洽，这可能对银河系化学演化模型提出质疑．因此，河外ＨⅡ区中氦丰度和高红移吸收云中氘丰度的测量及Ｄ和３Ｈｅ丰度化学演化的研究值得重视．     

我们所认识的宇宙

本银系是指我们所在的银河系，所有肉眼可见的星体及天上的银河（见图1）都属于这一银河系，直到1918年以前，天学家还认为太阳系在我们银河系的中心。从可观察到的星之分布来说的确如此；这是因为大部分的星集中在银河系盘面附近，而盘面上有许多尘埃可以吸收、散射可见光，以致离我们较远的星我们看不到。     

银河系的形成和演化

银河系是宇宙中数以百亿计星系中的一员.自威廉.赫歇尔以来,人们对银河系结构和运动状态的认识已有200多年历史,而有关银河系起源和演化的探索则只是在最近半个多世纪内才成为天文学的研究热点.文章在简述银河系认识史的基础上,对有关银河系形成和演化这一重要天体物理问题做了概要的评述,其中包括银河系厚盘的发现及其可能的形成机制.     

非旋转银河系的重力不稳定性

银河系中星体分布的重力不稳定性在天文物理是个熟知的问题.尝试以加速器物理的方法初步分析了这个现象, 得到非旋转银河系在它的大小超过某阈值时会呈现不稳定现象的结论,而此阈值与银河系的质量密度有关.     

寻找黑洞

恒星在死亡时将发生什么变化？这是天文学上一个非常自然的问题．自从３０年代以来，已经提出了各种理论来回答这一问题。这些理论预言有超新星、白矮星、中子星和黑洞的存在，前两个已是现在比较熟悉的天体了．１９６８年发现了脉冲星，它被证认为比寻常恒星致密得多、引力场强得多的自转中子星．可是大质量恒星在中子星状态也不可能是稳定的，它的末期演化到什么状态？有没有比中子星更致密、引力场更强的天体存在？这些问题都涉及到这些预言中最奇特、最不易理解的黑洞概念． 什么是黑洞呢？简单地说，黑洞就是一个其逃逸速度超过光速的…     

Dark-matter annihilation in the Galaxy

The possibility of amplification of the annihilation signal from dark matter in the Galaxy halo due to its clusterization into small-mass clumps (about the Moon’s or Earth’s mass) is discussed. Formation of dark-matter clumps is considered within the conventional cosmological model taking into account their hierarchical clustering and tidal destruction. It is shown that the amplification factor of γ rays from dark-matter annihilation due to small-mass clumps in the Galaxy may range from 10 to 1000.     

Galactic emissions: seeing through the Galaxy

The diffuse matter in our Galaxy is certainly to be damned by the cosmologist because it pollutes the CMB sky with the various emissions from its components: dust, ionised gas (free–free) and energetic particles (synchrotron). We detail here our knowledge, but also the unknowns, regarding these radiation sources. As we are not in a position to be able to physically escape our Galaxy, the better knowledge of these foreground components is our only hope to build a consistent model which will at least allow us a virtual escape. However, the detailed understanding of the physics of the different emissions and of the large scale distribution of the various emitters is a delight for many of us. We will show here some aspects, with a peculiar emphasis on a possible emission from tiny rotating grains. To cite this article: M. Giard, G. Lagache, C. R. Physique 4 (2003).     

Anti-helium flux as a signature for antimatter globular clusters in our Galaxy

The Alpha Magnetic Spectrometer experiment is shown to be sensitive to test the hypothesis on the existence of antimatter globular cluster in our Galaxy. The hypothesis follows from the analysis of possible tests for the mechanisms of baryosynthesis and uses antimatter domains in the matter-dominated Universe as the probe for the physics underlying the origin of matter. The interval of masses for the antimatter in our Galaxy is fixed from below by the condition of antimatter domain survival in the matter-dominated Universe and from above by the observed gamma-ray flux. For this interval, the expected fluxes of anti-helium-3 and anti-helium-4 are calculated with account for their interaction with the matter in the Galaxy.     

Cosmic-ray propagation in the Galaxy

Summary More than 95 contributed papers on cosmic-ray transport and acceleration in the Galaxy were presented at the XXIV International Cosmic-Ray Conference. The present summary covers part of the rapporteur talk and reflects a personal view of the subject. Rapporteur talk given at the XXIV International Cosmic-Ray Conference, Rome, August 28–September 8, 1995.     

The spatial distribution of old neutron stars in the Galaxy

The spatial distributions of old neutron stars (NSs) with ages 109 to 1010 yr in our Galaxy are investigated by Monte Carlo simulation under two different initial random velocity models.It is found that the scale heights of the distribution increase with the Galactic radial distance.The location of the peak of the NS distribution is closer to the Galactic center than that of their progenitors.The results from our detailed numerical analysis reveal that there is resemblance between the simulated old NS distribution and the structure of the observed HI disk.     

Dark matter annihilation in the Galaxy

The awaited dark matter (DM) neutralino annihilation signal from the galactic halo crucially depends on the presence of small-scale clumps. A mass function of the DM small-scale clumps is calculated in the standard cosmological scenario. The final distribution of clumps in the Galaxy is influenced by their tidal destruction. The basic sources of clump destruction are (i) clumps of larger scales, (ii) the gravitational field of the galactic disk, (iii) the stars in the galactic bulge, and (iv) the stars in the galactic halo. The destruction of clumps due to their mutual tidal interactions is important at earl stages of hierarchical clustering and the galactic halo formation. The clumps surviving through the hierarchical clustering are continuously destroyed by interactions with the galactic disk and stars. It is shown that, among the Moon or Earth mass DM clumps surviving through the hierarchical clustering, only 20% will further survive near the Sun’s position mainly because of the tidal destruction by the galactic disk. This reduction of DM clump density significantly diminishes the expected DM annihilation signal from the galactic halo. The text was submitted by the authors in English.     

Fractional models of cosmic ray acceleration in the Galaxy

Possible formulations of the problem of the acceleration of cosmic rays in the interstellar galactic medium with fractional differential equations have been considered. The applied technique has been physically justified. A Fermi result has been generalized to the case of the acceleration of particles in shock waves in the supernovae remnants fractally distributed in the Galaxy.     

Extracting science from surveys of our Galaxy

Our knowledge of the Galaxy is being revolutionized by a series of photometric, spectroscopic and astrometric surveys. Already an enormous body of data is available from completed surveys, and data of ever-increasing quality and richness will accrue at least until the end of this decade. To extract science from these surveys, we need a class of models that can give probability density functions in the space of the observables of a survey – we should not attempt to ‘invert’ the data from the space of observables into the physical space of the Galaxy. Currently just one class of model has the required capability, the so-called ‘torus models’. A pilot application of torus models to understand the structure of the Galaxy’s thin and thick discs has already produced two significant results: a major revision of our best estimate of the Sun’s velocity with respect to the local standard of rest, and a successful prediction of the way in which the vertical velocity dispersion in the disc varies with distance from the Galactic plane.     

On the fractional derivative model of the transport of cosmic rays in the Galaxy

One of the models of the transport of cosmic rays in the Galaxy that is based on a fractional partial differential equation is criticized. A new model called the model of limited anomalous diffusion is proposed. Its main difference from the criticized model is that the finiteness of the velocity of particles is taken into account.     

基于最近邻方法的类星体与正常星系光谱分类

随着高质最CCD传感器技术的日渐成熟与广泛应用,以及许多大型巡天计划的相继实施,天体数据量极大,因此天体观测数据的自动识别、分析问题首当其冲.文章在原始测量空间使用最近邻方法(NN)研究了正常星系与类星体光谱的识别问题.正常星系和类星体属于河外天体,一般距离地球较远,其观测光谱会受到许多干扰,所以这两类天体光谱的分类在...