论文标题
{\ it gaia}时代的多波长绝对幅度和红色团星的颜色
Multiwavelength Absolute Magnitudes and Colours of Red Clump Stars in {\it Gaia} Era
论文作者
论文摘要
这项研究介绍了从Apogee和Galah Dr2选择的红色团块（RC）星星的绝对幅度和颜色的多波长研究，并与{\ it gaia} dr2 Astrestric Data和Multi-Wavellength Mopitimeptric数据相辅相成{\ IT {\ it Wise}天空调查。这些分析以不同的距离估计方法为中心，使用{\ iT gaia}三角可视性，（1/$ \ varpi $）和贝叶斯统计数据，以及化学定义的银河盘群体上的[$α$/fe] $ \ times $ \ times $ [fe times $ [fe/h]飞机。此类调查疑问，长期以来研究的人口对RC光度的影响。使用两种不同的距离估计方法，（i）化学薄和化学厚的圆盘RC恒星被证明具有不同的绝对幅度，而在所有光度带中的颜色保持不变。对于1/$ \ varpi $，随着银河系的变化，绝对幅度在-0.12和+0.13 mag之间变化。对于其他方法，发现绝对幅度的这种变化更大。 （ii）2MASS光度法的银河系的BESAN \ c cON种群合成模型，其中从薄盘到厚的圆盘之间发现了化学种群之间的绝对幅度差异。当结果彼此相比，模型中绝对幅度的差异大约是观测值的三倍。我们确认RC绝对幅度取决于银河系种群的$α$元素丰度。
This study presents the multi-wavelength investigation of the absolute magnitudes and colours of the red clump (RC) stars selected from APOGEE and GALAH DR2 combined catalogue which is complemented with {\it Gaia} DR2 astrometric data and multi-wavelength photometric data of {\it GALEX} GR6/7, SDSS DR7, {\it Gaia} DR2, 2MASS and {\it WISE} sky surveys. The analyses are centred on the different distance estimation methods using {\it Gaia} trigonometric parallaxes, (1/$\varpi$) and Bayes statistics, and chemically defined Galactic disc populations on [$α$/Fe]$\times$[Fe/H] plane. Such investigation questions the long studied problem of the population effects on RC luminosity. Using two different distance estimation approach, (i) chemical thin and chemical thick disc RC stars are shown to have different absolute magnitudes, while colours remain the same in all photometric bands. Absolute magnitudes vary between -0.12 and +0.13 mag for the 1/$\varpi$ with the change of the Galactic population. This variation in absolute magnitudes is found to be larger for the other method. (ii) The Besan\c con population synthesis model of Galaxy for 2MASS photometry, in which the absolute magnitude difference between chemical populations were found between -0.35 and -0.40 mag from thin disc to thick disc. When results compared with each other, differences of absolute magnitudes are about three times larger in the model than observations. We confirm that the RC absolute magnitudes depend on $α$-element abundances of Galactic populations.
