论文标题
OGLE-GAL-ACEP-091 - 首个已知的多模式异常cepheid
OGLE-GAL-ACEP-091 -- The First Known Multi-Mode Anomalous Cepheid
论文作者
论文摘要
异常的头虫（ACS）是金属缺陷的，核心螺旋的脉动星，质量在1.2-2.2 m_s范围内。直到最近，所有已知的AC都是纯单模脉动器。最近，基于光学引力透镜实验（OGLE）调查的光度计数据库，以多种径向模式的AC脉动 - OGLE-GAL-GAL-ACP-091-脉动的第一个候选者。我们分析了该对象，表明它实际上是三模式脉动器。它在彼得森图中的位置，通过傅立叶系数量化的光曲线形态以及从盖亚（Gaia）视差得出的绝对幅度与Ogle-Gal-Gal-Acep-091是AC是AC的假设一致。我们的线性脉动模型网格表明，Ogle-Gal-ACEP-091是1.8 m_s星，金属度约为[Fe/H] = -0.5 Dex。
Anomalous Cepheids (ACs) are metal-deficient, core-helium-burning pulsating stars with masses in the range 1.2-2.2 M_S. Until recently, all known ACs were pure single-mode pulsators. The first candidate for an AC pulsating in more than one radial mode - OGLE-GAL-ACEP-091 - was recently identified in the Milky Way based on the photometric database of the Optical Gravitational Lensing Experiment (OGLE) survey. We analyze this object showing that it is actually a triple-mode pulsator. Its position in the Petersen diagram, the light-curve morphology quantified by Fourier coefficients, and absolute magnitudes derived from the Gaia parallax are consistent with the assumption that OGLE-GAL-ACEP-091 is an AC. Our grid of linear pulsation models indicates that OGLE-GAL-ACEP-091 is a 1.8 M_S star with a metallicity of about [Fe/H] = -0.5 dex.
