论文标题
II型头孢菌作为恒星示踪剂和距离指示器
Type II Cepheids as stellar tracers and distance indicators
论文作者
论文摘要
II型头孢菌素既是其宿主星系中老年恒星种群的有用距离指标和示踪剂。我们总结了大麦芽云中II型头孢菌素的近红外观察结果，并讨论了其周期露光关系的绝对校准。与VISTA VVV调查中银河凸起中II型头孢菌素的近红外数据相结合，我们估计了与银河系中心的稳定距离。我们发现，II型头孢菌素跟踪球形对称的空间分布，具有椭圆形结构的可能证据，类似于RR Lyrae恒星。与Gaia和VVV正确的运动一起，发现II型头孢菌素可追踪银河凸起中旧的，贫困的运动型恒星种群。
Type II Cepheids are both useful distance indicators and tracers of old age stellar populations in their host galaxy. We summarize near-infrared observations of type II Cepheids in the Large Magellanic Cloud and discuss the absolute calibration of their Period-Luminosity relations. Combining with the near-infrared data for type II Cepheids in the Galactic bulge from the VISTA VVV survey, we estimated a robust distance to the Galactic center. We found that type II Cepheids trace the spherically symmetric spatial distribution with possible evidence of ellipsoidal structure, similar to RR Lyrae stars. Together with Gaia and VVV proper motions, type II Cepheids were found to trace the old, metal-poor, kinematically hot stellar populations in the Galactic bulge.
