论文标题
新的DA白色矮人模型ZZ CETI星星学
New DA white dwarf models for asteroseismology of ZZ Ceti stars
论文作者
论文摘要
Asterosology是推断白矮人（WD）星的进化状态和化学分层的强大工具，并探索导致其形成的物理过程。对于可变的H丰富气氛（DA）WDS（称为DAV或ZZ CETI星星）尤其如此。我们提出了DA WD模型的新网格，考虑了祖细胞和WD星的建模和输入物理学的最后进步，从而避免并改善了我们先前工作中ZZ CETI星星中使用的DA WD模型中存在的几种缺陷。这些新模型来自一种自洽的方式，其内部化学分布的变化是由平均分子量反演引起的所有核心化学成分的混合而导致的。此外，沿祖细胞演化的预期核燃烧历史和混合事件是考虑到第三条挖掘的发生的，这确定了后 - AGB和白矮星的核心和信封的性质，以及WD初始质量质量关系。我们新ZZ星模型的H信封范围从日志（M_H/M _*）= -4延伸到-5，到log（M_H/M _*）= -13.5。这首先允许对具有极薄H信封的ZZ CETI恒星进行地震学解决方案。我们的新型H燃烧后AGB模型可以预测ZZ CETI恒星恒星中心附近的O和C的化学轮廓与我们先前工作中使用的恒星大不相同。我们发现，$ g $模式的脉动周期和新模型的模式捕获属性与表征我们以前作品的ZZ CETI模型的脉动周期有很大不同，尤其是长时间的ZZ CETI模型。
Asteroseismology is a powerful tool to infer the evolutionary status and chemical stratification of white dwarf (WD) stars, and to explore the physical processes that lead to their formation. This is particularly true for the variable H-rich atmosphere (DA) WDs, known as DAV or ZZ Ceti stars. We present a new grid of DA WD models that take into account the last advances in the modeling and input physics of both the progenitor and the WD stars, thus avoiding and improving several shortcomings present in the set of DA WD models employed in the asteroseismological analyses of ZZ Ceti stars we carried out in our previous works. These new models are derived from a self-consistent way with the changes in the internal chemical distribution that result from the mixing of all the core chemical components induced by mean molecular-weight inversions, from $^{22}$Ne diffusion, Coulomb sedimentation, and from residual nuclearburning. In addition, the expected nuclear-burning history and mixing events along the progenitor evolution are accounted for, in particular the occurrence of third dredge-up, which determines the properties of the core and envelope of post-AGB and white dwarf stars, as well as the WD initial-final mass relation. The range of H envelopes of our new ZZ star models extends from log(M_H/M_*)= -4 to -5, to log(M_H/M_*)= -13.5. This allows, for the first time, to consider seismological solutions for ZZ Ceti stars with extremely thin H envelopes. Our new H-burning post-AGB models predict chemical profiles of O and C near the stellar centre of ZZ Ceti stars substantially different from those we used in our previous works. We find that the pulsation periods of $g$ modes and the mode-trapping properties of the new models differ significantly from those characterizing the ZZ Ceti models of our previous works, particularly for long periods.
