论文标题
表征银河前景I中进化的恒星种群I:辐射幅度,空间分布和P-L关系
Characterizing the Evolved Stellar Population in the Galactic Foreground I: Bolometric Magnitudes, Spatial Distribution and P-L Relations
论文作者
论文摘要
使用Maser Stellar信标的无线电活动提供了重要的信息,以表征银河恒星种群。目前,凸起的不对称和动力学进化(BAADE)项目正在调查SIO MASERS的红外线(IR)颜色选择的目标。这提供了一个进化的恒星样本,可用于使用视线速度和可能的VLBI正确运动来研究内部,光学遮挡的星系。为了将Baade样品用于运动学研究,应表征出色的人群。在这项研究中,BAADE靶标已与IR(2MASS)和光学GAIA样品进行了交叉匹配。通过探索这种交叉匹配的协同作用,以及Gaia的视差和灭绝地图,可以表征本地($ d <2 $ kpc)AGB星星。我们已经定义了由IR和光学调查的交叉匹配的Baade目标产生的20,111个来源的\ TextIt {Baade-Gaia}样本。从该样品中,通过准确的视差测量,确认进化的恒星进化阶段的1,812颗恒星的样品,选择了太阳周围的2 kpc距离,以估算绝对(骨化)幅度。具有可变的Gaia的演变出的恒星种群似乎主要与中等光度($ 1,500^{+3,000} _ { - 500} \ l_ \ odot $)和250和1,250天之间的AGB恒星相关。
Radio campaigns using maser stellar beacons have provided crucial information to characterize Galactic stellar populations. Currently, the Bulge Asymmetries and Dynamical Evolution (BAaDE) project is surveying infrared (IR) color-selected targets for SiO masers. This provides a sample of evolved stars that can be used to study the inner, optically obscured Galaxy using line of sight velocities and possibly VLBI proper motions. In order to use the BAaDE sample for kinematic studies, the stellar population should be characterized. In this study, the BAaDE targets have been cross-matched with IR (2MASS) and optical Gaia samples. By exploring the synergies of this cross-match together with Gaia parallaxes and extinction maps, the local ($d < 2$ kpc) AGB stars can be characterized. We have defined a \textit{BAaDE-Gaia} sample of 20,111 sources resulting from cross-matching BAaDE targets with IR and optical surveys. From this sample, a~{\local} sample of 1,812 evolved stars with accurate parallax measurements, confirmed evolved stellar evolution stage, and within 2 kpc distance around the Sun was selected, for which absolute (bolometric) magnitudes are estimated. The evolved stellar population with Gaia counterparts that are variable seems to be predominantly associated with AGB stars with moderate luminosity ($1,500^{+3,000}_{-500} \ L_\odot$) and periods between 250 and 1,250 days.