标题： 太阳金属丰度低质量恒星的进化模型：质量-星等关系和颜色-星等图 显示英文标题

标题： Evolutionary models for solar metallicity low-mass stars: mass-magnitude relationships and color-magnitude diagrams

摘要： 我们提供了从0.075到1 $\msol$ 的低质量恒星的演化模型，适用于太阳类型金属丰度 [M/H]= 0 和 -0.5。 计算包括最新的内部物理和最新一代的非灰大气模型。 我们提供了两种金属丰度的质量-年龄-颜色-光度关系。 质量-M$_V$和质量-M$_K$关系与通过观测得出的经验关系非常一致。 理论颜色-光度图与球状星团（47 Tucanae）和开放星团（NGC2420 和 NGC2477）的序列进行了比较，这些星团是用哈勃空间望远镜观测的。 在$M_V$-$(V-I)$、$M_K$-$(I-K)$和$M_K$-$(J-K)$图中也进行了与场星序列的比较。 这些比较表明，低质量恒星大气模型的最新改进现在在近红外区域产生了可靠的恒星模型。 这些模型可用于金属丰度、质量、温度和光度的校准。 然而，在$T_{eff} \sim 3700K$以下的光学光谱区域仍存在不确定性，对于给定的星等，预测的 (V-I) 颜色偏蓝 0.5 星等。 这种差异的可能原因，最可能是光学区域缺少一种消光源以及尘埃形成的开始，已被详细研究。 显示英文摘要

摘要： We present evolutionary models for low mass stars from 0.075 to 1 $\msol$ for solar-type metallicities [M/H]= 0 and -0.5. The calculations include the most recent interior physics and the latest generation of non-grey atmosphere models. We provide mass-age-color-magnitude relationships for both metallicities. The mass-M$_V$ and mass-M$_K$ relations are in excellent agreement with the empirical relations derived observationally. The theoretical color-magnitude diagrams are compared with the sequences of globular clusters (47 Tucanae) and open clusters (NGC2420 and NGC2477) observed with the Hubble Space Telescope. Comparison is also made with field star sequences in $M_V$-$(V-I)$, $M_K$-$(I-K)$ and $M_K$-$(J-K)$ diagrams. These comparisons show that the most recent improvements performed in low-mass star atmosphere models yield now reliable stellar models in the near-infrared. These models can be used for metallicity, mass, temperature and luminosity calibrations. Uncertainties still remain, however, in the optical spectral region below $T_{eff} \sim 3700K$, where predicted (V-I) colors are too blue by 0.5 mag for a given magnitude. The possible origins for such a discrepancy, most likely a missing source of opacity in the optical and the onset of grain formation are examined in detail.