本文章最後由 iheby 於 2015-2-18 18:56 編輯
研討會: Prospects for Chemically Tagging Stars in the Galaxy @中文大學物理系
2015.02.09(一) 15:30 - 16:30
地點:香港中文大學 科學館北座 G26室
講者:Mr. Yuan-Sen TING (美國哈佛大學)
Despite many years of theorizing, the formation and evolution of galaxies remain one most the most important unsolved problems in astronomy.
The formation of galaxies involves turning gas into stars. A basic question is in what size of aggregates stars form. Since star clusters are shortlived, most clusters dissolve in less than 10Myrs. For this reason, the study of young open clusters is only probing the Galactic condition at the present time. Moreover, as the timescale of galaxy-assembling processes is typically less than 100Myrs, most of the kinematic and phase space information is lost. The idea of chemical-tagging is to find stars that share similar elemental abundances. Stars that were formed in the same protocloud should share similar elemental abundances. Therefore, by searching for stars that locate at the same point in the elemental abundance space, in principle, we should be able to reconstruct disrupted clusters. In this talk, Mr. Ting will discuss a forward model of chemical-tagging and explore what are the things that could be achieved in the on-going surveys such as APOGEE, GALAH, Gaia-ESO and LAMOST.
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