早期光譜型恆星的分佈與運動：古德帶分析

The Distribution and Kinematics of Early Type Stars：An Analysis of The Gould Belt

邱惠玲(Huey-Ling Chiou)

指導教授 ： 傅學海

國立臺灣師範大學/理學院/地球科學系/碩士(2001年)

摘要

無資料

關鍵字

古德帶 ； 銀河運動 ； 銀河系 ； 依巴羅斯 ； 第谷 ； 早期星

並列摘要

The distribution of the brightest stars on the sky looks like a great circle, known as Gould belt from Gould’s research about one century ago. From Hipparcos catalogue and the database enclosed, some early type stars, O, B, and A0 - A5, are selected to analyze to fit the Gould Belt. The distribution and kinematics of these selected stars are used to find information of Gould Belt.
Because the amounts of A type stars spreading on the galactic plane are much more than those O and B type stars, the Gould Belt is not obviously seen. From the distribution of the stars, the Gould Belt likely forms a ring region which is a flat inclining about 16.5 degree to the galactic plane and whose major axis is in the direction of l = 38 degree and 218 degree. In addition, the parallax, proper motion, and radial velocity are combined to find the solar motion with respect to OB stars and A0-A5 stars. Whether the Gould Belt was formed in the explosive event or in the impact event of a high velocity cloud, the members of the Gould Belt should still reserve several information of the velocity, which is different from that of the disk stars. Therefore, the property of the Gould Belt could be found out according to the different kinematical character. The Gould belt could be reflected by space position usually for OB stars, however, the Gould belt is also reflected roughly for main sequence stars with spectral down to A5. If the edge of the Gould Belt could be indexed by early type stars, the late type stars might be used to index larger scale understanding of the Gould Belt. Furthermore, the kinematical characteristic, proper motion or space velocity, is helpful to stand out the Gould Belt in the research. Two groups are seen clearly by eyes from the proper motion vector point diagrams of OB stars, and one could be with relation to the Gould Belt.

並列關鍵字

Gould belt ； galactic kinematics ； the Milky Way ； Hipparcos ； Tycho ； early type star