太阳系动力学中当前的重要课题

以当前太阳系动力学中的重要课题以及研究方法进行讨论，并提出一些看法，课题中主要讨论动力学模型，轨道共振，行星环，混沌和长期演化，近地天体运动，Kupiper带，太阳系中的引力理论，以及其他有关问题。     

关于太阳系小天体轨道演化的算法研究

太阳系小天体的运动对应—哈密顿(Hamilton)系统,对其轨道演化的数值研究宜采用哈密顿算法(即辛算法)。本文将仔细讨论这一问题,并以主带小行星的运动为例,较系统地介绍几种辛算法对应的显式辛差分格式。     

南京大学太阳塔CCD成像光谱观测系统和初步观测结果

本文介绍南京大学太阳塔的ＣＣＤ成像光谱观测系统的结构，工作方式，给出了该系统的一些性能测试结果，作为应用该系统的实例，文中给出了根据该系统观测的二维光谱资料，经处理得到的一个Ｈａ耀斑在线心和不同偏带处单色像的变化过程，该耀斑的亮度场轮廓图和速度场轮廓图。     

RECONSTRUCTING THE SOLAR CORONAL MAGNETIC FIELD AS A FORCE-FREE MAGNETIC FIELD

We present some preliminary results on different mathematical problems encountered in attempts to reconstruct the coronal magnetic field, assumed to be in a force-free state, from its values in the photosphere. We discuss the formulations associated with these problems, and some new numerical methods that can be used to get their approximate solutions. Both the linear constant- and the nonlinear cases are considered. We also discuss the possible use of dynamical 3D MHD codes to construct approximate solutions of the equilibrium force-free equations, which are needed for testing numerical extrapolation schemes.     

关于太阳系中光压对各种天体运动的影响问题

关于太阳辐射（简称光压）对各种天体（大行星、小行星、慧星以及各类航天器）运动的影响,本文从较完整的力学模型着手,作了详尽的分析,其结论是：由于太阳辐射相对较弱,而辐射压的作用大小还取决于承受天体的有效面质比,对太阳系中各自然天体（包括慧星的一些物理现象）运动的影响并不重要,而对各类航天器运动的影响却是不可忽视的。中文给出的力学模型和相应的研究方法,在一定条件下同样适用于强辐射的天体系统。     

IDENTIFICATION OF THE SOLAR SOURCE FOR THE 18 OCTOBER 1995 MAGNETIC CLOUD

It is necessary to identify signatures of solar sources in order to improve predictions of solar-caused geomagnetic activity. This is not a straightforward task as the relationship is not well understood. We apply an algorithm, derived from numerical simulations to identify the solar source of an interplanetary event that was observed by the WIND spacecraft on October 18, 1995 and was followed by a geomagnetic storm. No specific geomagnetic activity had been predicted at Space Weather Operations (SWO) in Boulder, CO, on the basis of earlier solar observations. The algorithm is used to estimate the time and location of the expected solar source of this interplanetary event. A review of solar observations prior to the WIND observations showed that solar activity precursors could be identified. A long-duration-event was seen by GOES in soft X-rays at the same time as a type IV burst was observed in metric radio wavelengths, and a rearrangement of fields was observed by the soft X-ray telescope on the Yohkoh satellite. This suggests that the algorithm is useful for post facto identification of solar sources, and that such combinations of solar activity should be further investigated for use in geomagnetic forecasting.     

太阳系P型逆行小天体运动的稳定区域问题

本文讨论了太阳系Ｐ型逆行小天体运动的稳定区域问题，首先，指出了Ｐ型逆行小天体顺行小天体的Ｈｉｌｌ稳定区域及数值稳定区域的差别，然后，讨论了大行星间Ｐ型逆行小天体存在的可能性问题。     

太阳射电望远镜远程控制系统

本文简要介绍了云南天文台１０ 米口径的太阳射电望远镜天线的远程控制系统中局域网控制和通过电话线控制的实现方案     

THE SOLAR MAGNETIC FIELD IN THREE DIMENSIONS

Historically, our understanding of the solar magnetic field has been shaped by an interplay between theoretical ideas about the subsurface dynamo and precise measurements of magnetic flux at the level of the photosphere. Today we have an unprecedented ability to measure, or to infer from measurements, properties of the magnetic field at every level from the solar interior to interplanetary space, although photospheric observations still lead the way in completeness and precision. I review the state of our capabilities to measure or calculate the magnetic field and suggest that the next major goal should be to follow specific magnetic structures in space and time from before they emerge until they can no longer be detected at any level.     

SOLAR ACTIVITY AS A RESULT OF TWO-WAVE MAGNETIC FLUX GENERATION

Solar activity has been studied by using the time series of the yearly mean Wolf sunspot numbers. It was shown that the long-term variation of solar activity could be interpreted both as a beat between the two wave magnetic flux with 21.5-yr and 19.3-yr periods and the epochs of low solar activity after the phase failure. This magnetic flux is likely to be generated by the torsional oscillations of the transition layer located at the bottom of the Sun's convection zone.The periodicities of solar cycles obtained allow us to predict the Sun's activity in the 21st century with high probability. In particular, cycle 23 is predicted to start in 1999 and its maximum to occur between mid-2005 and mid-2006, the Wolf number being in the interval 50–65.     

大行星内部能源问题

根据宇宙飞船等对巨行星观测结果,我们首次发现大行星(包括巨行星和地球)的光度随其质量存在有规律地变化。我们利用线性回归律,求出大行星的质-光关系式。它能为大行星能源探索提供某些重要线索和限制条件。其次,我们讨论了目前解释此能源的各种理论及其存在困难。最后,着重介绍一种新的热核反应机制。它不仅对超高温的而且对低温的聚变等离子体都适用。原来老的热核反应机制只是它的一个特例。它不仅能说明大行星内部能源问题,而且能解释实验室中和天体上观察到许多异常核聚变现象。我们发现:虽然这些异常现象在自然界表现形式各式各样,但是它们的基本原理都是相同的,即都可用新的热核反应机制来解释它们。     

STATISTICAL PROPERTIES OF THE PULSES IN THE SOLAR p-MODE POWER

We have revealed the periods of good visibility for each individual mode of low spherical degree using irradiance data from the IPHIR experiment. Their statistical properties and the influence on the resulting line shapes are discussed. The analysis of the temporal change of each mode power by Fourier transform with a running temporal window was performed. The running mean power of p-modes (=0, n=17–24 and =1, n=16–23) apparently changes with the rotation of the Sun. There is well visible an anticorrelation of the p-mode power with the mean solar magnetic field and less significant correlation with daily sunspot number.     

太阳大气中矢量磁场信息的推导

一种能从观测到的斯托克斯轮廓中提取太阳表面矢量磁场信息的方法在本文中提出，它利用斯托克斯轮廓非线心的极值点处相应参量对波长的导数为零这一数学事实，假设表面附近磁场矢量及热力学参量的变化梯度足够小以致所考虑的极值点的波长位置不随深度改变或此变化呆忽则使得偏振辐射围方程组得到极大的简化；再应用数值方法从此简化方程组中解出辐射表面附近的磁场矢量参数。通过拟合理论轮廓表明该法确实可以得到表面近似的磁场矢量     

太阳活动预报中的模糊识别综合指数

在太阳活动预报中,预报因子的选取和处理对预报效果影响甚大。本文在云台原有的平均综合指数基础上,运用模糊识别方法,给出了一种模糊识别综合指数,它能更好地表征太阳日面活动区的活动特征。这种方法简单、方便,较充分地利用了预报因子中所含有的有用信息,从而使识别预报率有所提高。     

EQUILIBRIUM CONDENSATION IN A SOLAR NEBULA

In attempts to reconstruct the environment of condensation of solar system materials, particularly exemplified by certain meteorite components, the relative temperatures of the gas and the solid are of critical importance. The relationships that determine the heat balance in a circumsolar grain-gas system are examined. Fundamental considerations show that regardless of opacity or gas density, the gas will always be at a higher temperature than the solid in such regions of the system where condensation is possible. Implications of the characteristic temperature differential between the gas and the condensing solid are discussed.     

INTER-CYCLE VARIATIONS OF SOLAR IRRADIANCE: SUNSPOT AREAS AS A POINTER

Most of the present models and reconstructions of solar irradiance use the concept of Photometric Sunspot Index (PSI) to account for the influence of sunspots on solar brightness. Since PSI is based on measured sunspot areas a firm database of such areas is essential. We show, however, that a significant disagreement exists between the data provided by the Royal Greenwich Observatory (from 1874 to 1976) and newer measurements provided by the observatories of Rome, Yunnan, Catania, and the US Air Force. The overlap of the time intervals over which sunspot areas were measured at Greenwich and Rome allows us to quantify the difference between the Greenwich and other data sets. We find that the various data sets differ, at least in a statistical sense, mainly by a correction factor of between 1.15 and 1.25.The revised time series of sunspot areas correlates well with the Zürich sunspot relative numbers over the last 120 years, with the relationship between sunspot areas and sunspot numbers changing only slightly from one cycle to the next. In particular, no indication exists for any extraordinary magnetic behavior of the Sun during the last 2 decades, as might falsely be concluded if the various sunspot area data sets are uncritically combined. There are, however, some indications that cycles 15 and 16 deviate from the rest. We expect that our results should have a significant influence on the reconstruction of the historical solar irradiance.     

THE RESONANT ABSORPTION OF 5-MIN OSCILLATIONS IN THE SOLAR ATMOSPHERE

The model calculations of 5-min solar oscillations are performed with consideration for the presence of canopy magnetic field in the solar chromosphere. It is shown that the occurrence of Alfvén resonances for 5-min oscillations in the solar chromosphere leads on the one hand to some change of the 5-min oscillation frequencies (up to a few µHz), and on the other hand to the heating of the chromosphere. The acoustic energy flux incoming to the chromosphere is of order 1 × 10 5 erg cm-2 s-1.     

太阳耀斑磁重联的数值模拟

数值模拟了太阳耀斑中二维磁重联过程。结果表明,当重联Ｘ 点比较高时,演化过程能再现双带耀斑中耀斑环的运动等主要特征;当重联Ｘ 点比较低时,可解释致密耀斑的观测特征。结果还表明,耀斑环上升和重联点上升之间没有直接的联系。