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简要地阐述了恒星光电测光工作中的常规数据处理方法及应该注意的一些问题。对食双星电测光这一领域的观测数据处理进行了概述,给出了ＢＶ双色光电测光观测数据处理软件包的编程思想及具体实现。最后介绍了这个软件包的使用情况和结果。 相似文献
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回顾了恒星表面结构多普勒成像研究工作的发展历史,重点评述了该项技术在类太阳活动恒星研究领域的应用。介绍了该项技术在国际上的发展现状,给出了恒星表面黑子结构形态的多普勒成像技术的基本原理,讨论了该项技术对观测仪器、观测过程和观测对象的要求,并对未来这一领域的研究工作进行了展望。 相似文献
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双星间的快速物质交换是一个非常复杂的过程,它涉及到双星演化的两个基本问题:物质交换的动力学不稳定性和公共包层的形成和演化.这两个问题是双星演化中最不清楚的两个基本问题.本论文通过建立相互作用双星之间的快速(绝热)物质损失模型,研究双星演化中物质交换的不稳定性判据和对公共包层的演化结局作出理论限制.利用恒星绝热物质损失模型得到的结果,还有很多潜在应用.比如,促进含双星的大样本恒星演化研究,改进演化星族合成方法等.恒星绝热物质损失模型的建立,基于主星在快速物质损失过程中,恒星内部的热量来不及交换, 相似文献
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回顾了恒星表面结构多谱勒成像研究工作的发展历史,重点评述了该项技术在类太阳活动恒星研究领域的应用。介绍了该项技术在国际上的发展现状,给出了恒星表面黑子结构形态的多普勒成像技术的基本原理,讨论了该项技术对观测仪器、观测过程和观测对象的要求,并对未来这一领域的研究工作进行了展望。 相似文献
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欧洲计划在2009年发射“赫歇尔”（Herschel）空间望远镜,其镜片直径达3.5米,远超哈勃空间望远镜（镜片直径为2.4米）,它将成为有史以来最大的空间望远镜。威廉·赫歇尔是18世纪著名的天文学家,他不仅发现了天王星,还开创了恒星天文学,他研究并假设（某些）星云是由恒星组成,提出著名的恒星演化学说;他不仅在天文望远镜的发展史上留下永不磨灭的足迹,而且是当时最伟大的观测天文学家,为恒星天文学的建立奠定了第一块基石,在天文学史上他被誉为“恒星天文学之父”。 相似文献
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恒星尘埃的实验室研究--实验天体物理学 总被引：1，自引：0，他引：1
原始球粒陨石含有来自恒星的微小固体颗粒(微米级),这些尘埃的同位素组成与太阳系物质截然不同,它们是目前唯一能直接获得的恒星固体样品．已发现的恒星尘埃有金刚石、石墨、碳化硅、刚玉、尖晶石、氮化物、和硅酸盐等,它们的母体恒星包括红巨星,AGB恒星、新星和超新星．对恒星尘埃的研究,使得更深入地了解星系的化学演化历史、恒星内部的核反应和湍流机制、恒星大气中尘埃的形成、星际介质物理现象等．恒星尘埃把天体物理领域延伸到了微观世界,它有机地结合了地球化学实验技术和天体物理理论,开辟了一门崭新的天文学分支实验天体物理学． 相似文献
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对1995年至2001年《Natue》和《Science》上发表的天文学论文的统计表明，行星天文学领域的论文数量明显超过天文学的其它分支学科，占天文学总论文数的1/3左右。从这个角度来看，行星天文学是天文学最活跃和重要的分支学科之一。对这些论文具体内容的分析可以给出当前行星天文学领域的若干热点问题。相比之下，我国对这一重要领域的关注和投入还远远不够。 相似文献
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中国古代天文学曾经取得过许多光辉成就,在世界天文学史上占有重要地位。正因为如此,已引起国内外有关学者的注意和重视。不断进行研究,有大量论著发表。最近有幸读到了上海学林出版社出版的潘鼐先生的新著《中国恒星观测史》,感到非常高兴。这部有74万多字的著作,不仅在中国恒星观测史研究方面是一部不可多得的好书,而且也是近年来中国天文学史研究方面的一部优秀学术专著。现特简评如 相似文献
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双星轨道拟合是天文学的一项基础性研究工作。其主要目的是给出双星系统的二体轨道参数,这些参数不仅是高精度、高网格密度星表参考架的必要组成部分,而且也为理解各种有关观测现象提供了必要的动力学基础;更重要的是,双星轨道拟合可以直接估计恒星物理和星系天文学等领域极有应用价值的恒星质量参数。因此,长期以来双星轨道拟合工作一直受到研究者的广泛关注。近年来,随着高精度的恒星运动学观测资料的大量积累,双星轨道拟合更成为天体测量和天体力学的一个共同的热点课题,有关研究也有了长足的进展。综述了双星轨道拟合的历史及现状,其中着重介绍了目前所用的主要观测资料和各种具体的拟合模型、拟合方法;简要描述了几种主要的双星星表;展望了今后双星轨道拟合工作的发展趋势。 相似文献
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L. G. Kiseleva J. Colin B. Dauphole & P. Eggleton 《Monthly notices of the Royal Astronomical Society》1998,301(3):759-766
In this paper we present numerical results on the decay of small stellar systems under different initial conditions (multiplicity 3 ≤ N ≤ 10, and various mass spectra, initial velocities and initial configurations). The numerical treatment uses the CHAIN1 code (Mikkola &38; Aarseth). Particular attention is paid to the distribution of high-velocity escapers: we define these as stars with velocity above 30 km s−1 . These numerical experiments confirm that small N -body systems are dynamically unstable and produce cascades of escapers in the process of their decay. It is shown that the fraction of stars that escape from small dense stellar systems with an escape velocity greater than 30 km s−1 is ∼1 per cent for all systems treated here. This relatively small fraction must be considered in relation to the rate of star formation in the Galaxy in small groups: this could explain some moderately high-velocity stars observed in the Galactic disc and possibly some young stars with relatively high metallicity in the thick disc. 相似文献
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T. Kogure 《Astrophysics and Space Science》1986,118(1-2):39-43
The cooperation programme in astronomy between Indonesia and Japan is presented as an example of a well-coordinated bilateral cooperation between Asian countries. This cooperation has started in 1979, in the fields of galactic astronomy and stellar physics. The form of the cooperation is principally the exchange of persons between both countries for the purposes of collaborative works in some specific fields, the training of young astronomers, and technical cooperation. The main subjects of collaborative works are: (1) survey of red giants in the galactic center region, (2) survey of H-emission stars in some areas of the sky, (3) theoretical study of the dynamical evolution of stellar systems, (4) photoelectric observations of southern close binaries, (5) X-ray binaries and pulsars, (6) Be stars, and (7) other topics. The organization and main results of these works are presented, along with a future aspect of the cooperation.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献
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A.E. Lynas-Gray 《Astrophysics and Space Science》2004,291(3-4):197-203
Studies in extragalactic astronomy, galactic structure and the late stages of stellar evolution provide ample motivation for surveys of fields in the Galactic Halo. Apart from white dwarfs, blue stars had been regarded as luminous objects confined to star-forming regions in the Galactic Plane; finding them at high galactic latitudes attracted immediate interest, because their luminosities were intermediate between those of white dwarfs and blue Main Sequence stars. The study of blue stars away from the Galactic Plane was initiated by Greenstein; in due course effective temperatures (T e ff), surface gravities (log g) and abundances showed these stars form what appeared to be a blue extension of the known Horizontal Branch (HB) in the Hertzsprung–Russell Diagram. Extended Horizontal Branch (EHB) stars were identified with Extreme Horizontal Branch stars in globular clusters. It was realised that HB and EHB stars must have formed as a consequence of mass-loss on the Giant Branch, either at or before the helium flash. Mass-loss on the Giant Branch leading to the formation of EHB stars was considered more likely for stars in binary systems. The scene was then set for three decades of EHB star research. 相似文献
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Riccardo Giacconi 《Experimental Astronomy》2009,25(1-3):143-156
The development of X-ray telescopes over the last 45 years is briefly summarized. The first applications to the study of solar X-ray emission are described up to the 1973 Skylab mission. The rather convoluted path that led to the first stellar X-ray orbiting telescope Einstein (1978) and later to Chandra (1999) are discussed. During this 45 years period the angular resolution improved from 20 to 0.5 arc sec and the sensitivity by ten billions. X-ray observations have discovered new types of stellar systems (binary X-ray sources containing neutron stars and black holes) and intergalactic high temperature plasmas containing most of the baryonic mass of the universe. They have become an indispensable tool to study the role of energetic phenomena in the creation and dynamic evolution of cosmic structures. The methodology introduced by X-ray astronomy has influenced all of astronomy. 相似文献
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The dynamical evolution of small stellar groups composed of N=6 components was numerically simulated within the framework of a gravitational N-body problem. The effects of stellar mass loss in the form of stellar wind, dynamical friction against the interstellar medium, and star mergers on the dynamical evolution of the groups were investigated. A comparison with a purely gravitational N-body problem was made. The state distributions at the time of 300 initial system crossing times were analyzed. The parameters of the forming binary and stable triple systems as well as the escaping single and binary stars were studied. The star-merger and dynamical-friction effects are more pronounced in close systems, while the stellar wind effects are more pronounced in wide systems. Star-mergers and stellar wind slow down the dynamical evolution. These factors cause the mean and median semimajor axes of the final binaries as well as the semimajor axes of the internal and external binaries in stable triple systems to increase. Star mergers and dynamical friction in close systems decrease the fraction of binary systems with highly eccentric orbits and the mean component mass ratios for the final binaries and the internal and external binaries in stable triple systems. Star mergers and dynamical friction in close systems increase the fraction of stable triple systems with prograde motions. Dynamical friction in close systems can both increase and decrease the mean velocities of the escaping single stars, depending on the density of the interstellar medium and the mean velocity of the stars in the system. 相似文献
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A. Collier Cameron 《Astrophysics and Space Science》1998,261(1-4):71-80
I review recent progress in the field of stellar surface imaging, with particular reference to advanced methods for mapping
surface-brightness inhomogeneities and the surface vector magnetic field on magnetically active late-type stars. New signal
enhancement techniques, utilising profile information from hundreds or thousands of photospheric lines simultaneously, allow
images to be derived for stars several magnitudes fainter than was previously possible. For brighter stars, the same techniques
make it possible to map features as small as two or three degrees in extent on the stellar surface. This opens up whole new
areas of research, such as the ability to use starspot tracking to study surface differential rotation patterns on single
and binary stars, and to follow the secular evolution of the magnetic field itself.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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I. I. Romanyuk 《Astrophysical Bulletin》2017,72(3):286-304
We have analyzed more than 90 papers in the area “Magnetic fields and physical parameters of chemically peculiar and related stars,” published mainly in 2016. The main results of the period under survey are as follows. The search for new magnetic stars continued.Many measurements weremade at the 6-m BTA telescope of the SAO RAS, new data on stellar magnetism in the OrionOB1 association were obtained. A systematic study ofmagnetic fields of stars with large anomalies in the energy distribution in the continuum was started. New data on ultra-slowmagnetic rotators—chemically peculiar stars with rotation periods of years and decades are obtained. Successful observations on the search for new magnetic stars are performed among the objects of the southern sky in Chile at the FORS2 VLT spectropolarimeter. A new direction was developed, namely, the study of binarymagnetic stars. Depending on the mass–distance ratio between the components, interaction with the magnetosphere and, possibly, magnetic braking may occur. The study of the details of this process is important for the theory of formation of stellar magnetic fields. The search for large-scale, but weak magnetic fields (magnitude of unities and tens of G) in non-CP stars is ongoing. Such fields are found in Am stars. No fields were found in the classical Be stars. Cool stars of various types were studied in detail. They manifested magnetic fields of a complex structure. Their mapping was performed, changes in the topology of the field were found at timescales of several years. Spectral and photometric variability was studied. Dozens of new potentially magnetic stars are discovered as a result of the ASAS-3, SuperWASP, Stereo and Kepler surveys. High-accuracy observations of rapidly oscillating stars were performed with the BRITE nanosatellite.Work continued on the studies of magnetic and photometric variability of white dwarfs. Finally, an overview of several papers on exoplanets, related with the subject of our study is presented. 相似文献
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Daniel Malmberg Francesca De Angeli Melvyn B. Davies Ross P. Church Dougal Mackey Mark I. Wilkinson 《Monthly notices of the Royal Astronomical Society》2007,378(3):1207-1216
The stars that populate the solar neighbourhood were formed in stellar clusters. Through N -body simulations of these clusters, we measure the rate of close encounters between stars. By monitoring the interaction histories of each star, we investigate the singleton fraction in the solar neighbourhood. A singleton is a star which formed as a single star, has never experienced any close encounters with other stars or binaries, or undergone an exchange encounter with a binary. We find that, of the stars which formed as single stars, a significant fraction is not singletons once the clusters have dispersed. If some of these stars had planetary systems, with properties similar to those of the Solar System, the planets' orbits may have been perturbed by the effects of close encounters with other stars or the effects of a companion star within a binary. Such perturbations can lead to strong planet–planet interactions which eject several planets, leaving the remaining planets on eccentric orbits. Some of the single stars exchange into binaries. Most of these binaries are broken up via subsequent interactions within the cluster, but some remain intact beyond the lifetime of the cluster. The properties of these binaries are similar to those of the observed binary systems containing extrasolar planets. Thus, dynamical processes in young stellar clusters will alter significantly any population of Solar System-like planetary systems. In addition, beginning with a population of planetary systems exactly resembling the Solar System around single stars, dynamical encounters in young stellar clusters may produce at least some of the extrasolar planetary systems observed in the solar neighbourhood. 相似文献
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Be单星和Be/X射线双星作为一类特殊早型天体和特殊的大质量X射线双星 ,在各个波段都有与其它相同光谱型的B型天体显著不同的特征 ,因此长期以来引起中外天文学者的关注。首先在可见光波段发射线的存在 ,就是对仅产生吸收线的经典大气的挑战 ;其次Be星作为一类早型带有包层天体 ,研究Be星包层的性质 ,对研究原恒星包层性质和进一步了解早型星其它光谱型的性质是非常重要的 ;再者可以研究Be星的存在与星际磁场或湍流的星际介质是否有关 ;最后研究Be/X射线双星 ,对双星的演化模型也有很重要的作用。随着天文观测手段的不断完善和理论模型的发展 ,我们对Be星的现象有了更深的了解 ,并且产生了一些模型。研究内容包括Be星包层和星风的性质 ,以及包层形成机制 ,Be/X射线双星物质相互作用等。本文共分五章 ,第一章主要概要介绍Be和Be/X射线双星历史和目前已经取得的成就 ;第二章介绍Be单星多波段观测结果 ;第三章介绍Be/X射线双星的观测结果 ;第四章介绍目前主要的Be单星和Be/X射线双星模型 ;第五章给出Be/X射线双星XPer/ 4U0 352 30的分光观测结果 ,并结合单臂振动盘模型给出定性解释。 相似文献