论文标题
北极星的奇怪情况：演化模型与北极星测量之间的持续张力
The Curious Case of the North Star: the continuing tension between evolution models and measurements of Polaris
论文作者
论文摘要
北极星是与我们最近的头脑，因此在我们对一般的头孢菌和Leavitt Law的理解中占有特殊的位置。在过去的几十年中，我们学到了许多关于星际恒星的新知识，也是多星系的主要组成部分。因此，我们更精确地测量了北极星的质量，半径和演变。但是，随着我们了解更多信息，越来越清楚我们了解较少。有证据表明，北极星比恒星进化模型所暗示的要小得多，并且北极星比其主要序列伴侣年轻得多。在这项工作中，我们回顾了最近的一些测量及其与过去研究的联系。然后，我们提出了新的恒星进化模型和种群合成计算，以与Evans等人的新质量测量值进行比较。 （2018）。我们发现北极星的质量差异约为50 \％。我们还发现，北极星与其同伴之间可能存在年龄差异，但是差异不是真实的可能性也很小。
Polaris is the nearest Cepheid to us and as such holds a special place in our understanding of Cepheids in general and the Leavitt Law. In the past couple of decades, we have learned many new things about the star as a Cepheid and as the primary component of a multiple star system. As such, we are more precisely measuring the mass, radius and evolution of Polaris. However, as we learn more, it is becoming clear that we understand less. There is evidence that Polaris is much less massive than stellar evolution models suggest and that Polaris is a much younger star than its main sequence companion. In this work, we review some of the recent measurements and their connections with past studies. We then present new stellar evolution models and populations synthesis calculations to compare with the new mass measurements by Evans et al. (2018). We find that the mass discrepancy for Polaris is about 50\%. We also find that there is a likely age discrepancy between Polaris and its companion, but that there is also a very small probability that the discrepancy is not real.
