X射线脉冲星4U 1538—52 的时间和能谱特性

本文处理分析了EXOSAT卫星对4U1538-524次中能观测资料,并结合其他观测结果对4U1538-52的时间和能谱特性作了分析和解释:中子星自转仍在减慢;能谱为幂律谱,Tenma卫星以后的观测未见Fe发射线;X射线dip现象可解释为一前景星对中子星的遮掩而形成;X射线爆发在不同的轨道位相出现,持续近1小时;在1keV附近似有一发射线。     

火箭发动机固体药柱的X射线照相检验

介绍复合包敷层厚壁固体药柱的Ｘ射线检验透照工艺的设计和检测结果的评价。可发现气孔和装药不均匀等缺陷,检测出的最小缺陷为φ３ｍｍ的气孔。     

Stellar Coronal Astronomy

Coronal astronomy is by now a fairly mature discipline, with a quarter century having gone by since the detection of the first stellar X-ray coronal source (Capella), and having benefitted from a series of major orbiting observing facilities. Serveral observational characteristics of coronal X-ray and EUV emission have been solidly established through extensive observations, and are by now common, almost text-book, knowledge. At the same time the implications of coronal astronomy for broader astrophysical questions (e.g.Galactic structure, stellar formation, stellar structure, etc.) have become appreciated. The interpretation of stellar coronal properties is however still often open to debate, and will need qualitatively new observational data to book further progress. In the present review we try to recapitulate our view on the status of the field at the beginning of a new era, in which the high sensitivity and the high spectral resolution provided by Chandra and SMM-Newton will address new questions which were not accessible before. This revised version was published online in August 2006 with corrections to the Cover Date.     

Coronal Mass Ejections

This workshop summary tries to distill the key difficulties and questions in the art of (I)CME physics and strategies to address them. (I)CMEs are multi-dimensional, multi-parameter, and multi-scale phenomena related to the solar dynamo, corona, and heliosphere. This workshop illustrates the immense progress made in describing and modeling these spectacular energetic solar events, but also shows clear shortcomings in our understanding of them.     

Black-hole transients: From QPOs to relativistic jets

Due to the impressive amount of new data provided by the RXTE satellite in the past decade, our knowledge of the phenomenology of accretion onto black holes has increased considerably. In particular, it has been possible to schematize the outburst evolution of transient systems on the basis of their spectral and timing properties, and link them to the ejection of relativistic jets as observed in the radio. Here, I present this scheme, concentrating on the properties of the quasi-periodic oscillations observed in the light curves and on the link with jet ejection.     

Observations of compact X-ray binaries with the Chandra X-ray Observatory

The Chandra X-ray Observatory was launched on July 23, 1999. The first X-ray photons were detected on August 12 of that same year. Subsequently observations with the Observatory, which features sub-arcsecond angular resolution, have revolutionized our understanding of the X-ray emitting sky providing hosts of spectacular energy-resolved images and high-resolution spectra. Here we present a brief overview of Chandra X-ray Observatory observations of compact X-ray binaries.     

Large light X-ray optics: basic ideas and concepts

One of the main guidelines for future X-ray astronomy projects like, e.g., XEUS (ESA) and Generation-X (NASA) is to utilize grazing-incidence focusing optics with extremely large telescopes (several tens of m² at 1 keV), with a dramatic increase in collecting area of about two order of magnitude compared to the current X-ray telescopes. In order to avoid the problem of the source's confusion limit at low fluxes, the angular resolution required for these optics should be superb (a few arcsec at most). The enormous mirror dimensions together with the high imaging performances give rise to a number of manufacturing problems. It is basically impossible to realize so large mirrors from closed Wolter I shells which benefit from high mechanical stiffness. Instead the mirrors need to be formed as rectangular segments and a series of them will be assembled in a petal. Taking into account the realistic load capabilities of space launchers, to be able to put in orbit so large mirror modules the mass/geometric-area ratio of the optics should be very small. Finally, with a so large optics mass it would be very difficult to provide the electric power for an optics thermal active control, able to maintain the mirrors at the usual temperature of 20 °C. Therefore, very likely, the optics will instead operate in extreme thermal conditions, with the mirror temperature oscillating between −30 and −40 °C, that tends to exclude the epoxy replication approach (the mismatch between the CTE of the substrate and that of the resin would cause prohibitively large deformations of the mirror surface profiles). From these considerations light weight materials with high thermal–mechanical properties such as glass or ceramics become attractive to realize the mirrors of future Xray telescopes. In this paper, we will discuss a segments manufacturing method based on Borofloat^TM glass. A series of finite element analysis concerning different aspects of the production, testing and integration of the optics are also presented as well.     

等分压常压累积检漏技术

通过对常用的大气压累积法氦质谱检漏过程的理论分析，指出了该方法可能的系统误差。分析认为：对于表面材料粘附几率较小的被检件，可以采用常用的大气压累积检漏方法进行总漏率的测量，而对于表面材料粘附几率较大的被检件（ 如表面存在大量的有机材料等） ，如采用常用的大气压累积检漏方法进行总漏率的测量必将带来较大的系统误差。最后，提出了消除该系统误差的等分压常压累积检漏技术，并与常用的常压累积法检漏技术进行了比较。     

X-rays from the first massive black holes

X-ray studies of high-redshift (z > 4) active galaxies have advanced substantially over the past few years, largely due to results from the new generation of X-ray observatories. As of this writing X-ray emission has been detected from nearly 60 high-redshift active galaxies. This paper reviews the observational results and their implications for models of the first massive black holes, and it discusses future prospects for the field.     

Fluid instabilities around accreting X-ray sources

Some aspects of fluid instabilities occurring in the magnetospheres of accreting neutron stars are discussed. It is pointed out that (i) in the absence of strong differential rotation, the accreting plasma should be drawn out into spiralling, sheet-like structures, resulting in efficient mixing between the two media; (ii) the Rayleigh-Taylor instability also acts to limit the X-ray luminosity in super-critical sources; and (iii) magnetic shear has a strong stabilizing influence on Kelvin-Helmholtz modes, and its presence may allow substantial amounts of material to be supported around the magnetosphere.