论文标题
限制在大麦芽云中用分辨出的恒星种群来限制热脉动渐近巨型分支阶段
Constraining the thermally pulsing asymptotic giant branch phase with resolved stellar populations in the Large Magellanic Cloud
论文作者
论文摘要
在天体物理学中,热脉冲渐近巨型分支(TP-AGB)相的可靠模型至关重要,包括我们对星系星系,宇宙粉尘产生和星际介质富集的光谱分布的解释。为了改善包括对TP-AGB阶段的详细描述的恒星等异源集,我们将最近对小麦芽云(SMC)中AGB种群的校准扩展到更丰富的大型大型麦哲伦云(LMC)。我们使用从Vista调查得出的空间分辨的恒星形成历史记录了LMC恒星群体,将LMC恒星群体建模。我们通过匹配星数和$ k _ {\ rm s} $ - 频段光度函数的AGB恒星在LMC中识别的$ k _ {\ rm s} $来表征第三条挖掘的效率。与以前的发现相一致,我们确认,与SMC相比,由于金属性较高,LMC AGB恒星中的第三次挖掘效率略低。 C富含C的初始质量的预测范围在$ M _ {\ rm I} \大约1.7-3〜 \ Mathrm {m} _ {\ odot} $ at $ z _ {\ rm i} = 0.008 $。我们展示了在碳恒星光谱中包含新的不透明度数据将如何提高模型的性能。我们讨论了校准模型的预测寿命,集成的亮度和质量损失率分布。我们的校准结果包括在公开可用的更新恒星等线孔中。
Reliable models of the thermally pulsing asymptotic giant branch (TP-AGB) phase are of critical importance across astrophysics, including our interpretation of the spectral energy distribution of galaxies, cosmic dust production, and enrichment of the interstellar medium. With the aim of improving sets of stellar isochrones that include a detailed description of the TP-AGB phase, we extend our recent calibration of the AGB population in the Small Magellanic Cloud (SMC) to the more metal rich Large Magellanic Cloud (LMC). We model the LMC stellar populations with the TRILEGAL code, using the spatially-resolved star formation history derived from the VISTA survey. We characterize the efficiency of the third dredge-up by matching the star counts and the $K_{\rm s}$-band luminosity functions of the AGB stars identified in the LMC. In line with previous findings, we confirm that, compared to the SMC, the third dredge-up in AGB stars of the LMC is somewhat less efficient, as a consequence of the higher metallicity. The predicted range of initial mass of C-rich stars is between $M_{\rm i} \approx 1.7 - 3~\mathrm{M}_{\odot}$ at $Z_{\rm i} = 0.008$. We show how the inclusion of new opacity data in the carbon star spectra will improve the performance of our models. We discuss the predicted lifetimes, integrated luminosities and mass-loss rate distributions of the calibrated models. The results of our calibration are included in updated stellar isochrones publicly available.