标题： 中等质量恒星：更新的模型 显示英文标题

标题： Intermediate mass stars: updated models

摘要： 在1.2到9 $M_{\odot}$ 的质量范围内，提出了一组新的恒星模型。 所采用的化学组成涵盖了典型的银河系值，即 $0.0001 \le Z \le 0.02$ 和 $0.23 \le Y \le 0.28$。 还讨论了最近几种类似恒星模型的比较。 主要结论是，各种演化结果之间的差异仍然相当大。 例如，我们发现氢燃烧演化时间可能相差高达20%。 对于氦燃烧阶段，分歧甚至更大（高达40-50%）。 由于各种输入物理和数值算法之间的联系可能会放大或抵消单一成分对最终恒星模型的影响，这些差异的来源并不明显。 然而，这些在演化轨迹中明显存在的差异，在等时线图上有所减少。 通过我们更新的模型，我们表明由恒星演化理论推导出的年龄与使用其他独立方法应用于邻近的疏散星团所得出的年龄非常一致。 最后，理论上的初始/终质量关系得到了修订。 显示英文摘要

摘要： A new set of stellar models in the mass range 1.2 to 9 $M_{\odot}$ is presented. The adopted chemical compositions cover the typical galactic values, namely $0.0001 \le Z \le 0.02$ and $0.23 \le Y \le 0.28$. A comparison among the most recent compilations of similar stellar models is also discussed. The main conclusion is that the differencies among the various evolutionary results are still rather large. For example, we found that the H-burning evolutionary time may differ up to 20 %. An even larger disagreement is found for the He-burning phase (up to 40-50 %). Since the connection between the various input physics and the numerical algorithms could amplify or counterbalance the effect of a single ingredient on the resulting stellar model, the origin of this discrepancies is not evident. However most of these discrepancies, which are clearly found in the evolutionary tracks, are reduced on the isochrones. By means of our updated models we show that the ages inferred by the theory of stellar evolution is in excellent agreement with those obtained by using other independent methods applied to the nearby Open Clusters. Finally, the theoretical initial/final mass relation is revised.