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arXiv 1702.04255astro-ph.GA
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用直接法测定电离气体星云的化学丰度

Ionized gaseous nebulae chemical abundance determination using the direct method

Enrique Pérez-Montero

摘要:

在本教程中,它是解释的程序来分析由大质量恒星形成电离星云产生的光学发射线光谱。特别是,它描述了用于获得物理性质,如电子密度和温度,以及离子丰度的最具代表性的元素,其发射线是存在于光谱的方法。本教程的重点是直接方法,基于电子温度的测量,推导出丰度,给定的电离和电离气体的热平衡是由金属丰度占主导地位。文中还给出了由某些离子的丰度计算总丰度的电离校正因子。最后,介绍了几种求丰度的强线方法。当无法得出温度估计值时使用这些方法,但如果对它们进行校准,则可以与直接方法一致。

英文摘要:

In this tutorial it is explained the procedure to analyze an optical emission-line spectrum produced by a nebula ionized by massive star formation. Particularly, it is described the methodology used to derive physical properties, such as electron density and temperature, and the ionic abundances of the most representative elements whose emission lines are present in the optical spectrum. The tutorial is focused on the direct method,based on the measurement of the electron temperature to derive the abundances, given that the ionization and thermal equilibrium of the ionized gas is dominated by the metallicity. The ionization correction factors used to obtain total abundances from the abundances of some of their ions are also given. Finally, some strong-line methods to derive abundances are described. These are used when no estimation of the temperature can be derived, but that can be consistent with the direct method if they are calibrated.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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