Catalog of Fundamental-Mode RR Lyrae Stars in the Galactic Bulge from the Optical Gravitational Lensing Experiment
Catalog of Fundamental-Mode RR Lyrae Stars in the Galactic Bulge from the Optical Gravitational Lensing Experiment
复制标题
光学引力透镜实验中银河核球中基本模式 RR 天琴座恒星的目录
DOI：
10.1086/507407
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发表时间：
2006
期刊：
影响因子：
--
通讯作者：
D. Fabrycky
中科院分区：
文献类型：
--
作者：
M. Collinge;T. Sumi;D. Fabrycky
我们提出了一个目录的1888个基本模式RR天琴座恒星检测的光学引力透镜实验（OGLE）的第二阶段的银河系隆起领域。该星表包括光变曲线的基本参数、Blazhko频率的识别、最低光下的V-I颜色（对于大多数恒星）以及每个星星的其他信息。我们检测到高发病率的Blazhko现象（至少27.6%），包括前所未有的许多频率三胞胎，我们归因于我们敏感的搜索方法。我们发现，最小光V-I颜色我们使用这种颜色来评估从OGLE数据得出的银河系隆起的红化图的零点精度，发现除了低水平的随机误差或分辨率效应外，（造成大部分散射），在大多数磁场中，该图可能系统地将E（V-I）过度表示约0.05 mag。我们提出了合理有力的证据表明，RR天琴座红色团块的颜色分离是由0.05-0.08等比本地的凸起，这主张谨慎使用这些恒星的红化测定。我们认为RR天琴座约束的银心距离，但绝对星等校准的不确定性留下了显着的灵活性的结果。与以前的结果相比，我们在经度±3°以内的天琴座RR星群中稳健地检测到银河棒的签名，我们强调了红团巨星和金属更贫乏的天琴座RR星所追踪的结构之间的明显差异。
We present a catalog of 1888 fundamental-mode RR Lyrae stars detected in the Galactic bulge fields of the second phase of the Optical Gravitational Lensing Experiment (OGLE). The catalog includes basic parameters of the light curves, identifications of Blazhko frequencies, V - I colors at minimum light (for most stars), and other information for each star. We detect a high rate of incidence of the Blazhko phenomenon (at least 27.6%), including unprecedentedly many frequency triplets, which we attribute to our sensitive search method. We find that the minimum light V - I color (useful as a reddening indicator) grows slowly redder with increasing period and exhibits a star-to-star scatter of approximately 0.07 mag. We use this color to evaluate the zero-point accuracy of the reddening map of the Galactic bulge derived from OGLE data and find that in addition to low-level random errors or resolution effects (responsible for much of the scatter), the map may systematically overrepresent E(V - I) by approximately 0.05 mag in most fields. We present reasonably robust evidence that the RR Lyrae-to-red clump color separation is larger by 0.05-0.08 mag in the bulge than locally, which argues for caution in the use of these stars for reddening determinations. We consider the RR Lyrae constraint on the Galactocentric distance, but uncertainty about the absolute magnitude calibration leaves significant flexibility in the result. In contrast to previous results, we robustly detect the signature of the Galactic bar in the RR Lyrae population within the inner ±3° of longitude, and we highlight the apparent differences between the structures traced by the red clump giants and the more metal-poor RR Lyrae stars.