Combined Effects of Rotation and Age Spreads on Extended Main-Sequence Turn Offs - Isochrones and Stellar Tracks

Theoretical isochrones and EEP stellar tracks featured in Gossage et al. 2019 (Combined Effects of Rotation and Age Spreads on Extended Main-Sequence Turn Offs). These 1D stellar evolution models are based on MESA r7503, and utilize the same physical assumptions as in MIST v1.0 (Choi et al. 2016). The models are described in Gossage et al. 2018 and Gossage et al. 2019\(^1\), but salient features include: Metallicities [Fe/H] = -0.45, -0.30, -0.15, 0.0, 0.15, 0.30, 0.45 (assuming Asplund et al. 2009 protosolar abundances \(\rm Z_{\odot}\) = 0.0142). Rotation rates from v/vcrit = 0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 (initiated at ZAMS) Masses from 0.1 to 8 solar masses with spacings of: \(\rm \Delta M = 0.05 M_{\odot}\) for \(\rm M < 1 M_{\odot}\) \(\rm \Delta M = 0.04 M_{\odot}\) for \(\rm 1 M_{\odot} \leq M < 2 M_{\odot}\) \(\rm \Delta M = 0.2 M_{\odot}\) for \(\rm 2 M_{\odot} \leq M \leq 8 M_{\odot}\) Models are evolved up to the first thermal pulse. File name convention: zip files, e.g., \(\texttt{MIST_v1.0_feh_p0.15_rotating_tracks.zip}\), contain theoretical models at a particular metallcity ([Fe/H] = 0.15 in this case), at all rotation rates and masses. The file \(\texttt{MIST_v1.0_feh_m0.15_rotating_tracks.zip}\) contains models at [Fe/H] = -0.15, and so on. \(\texttt{*_tracks.zip}\) contain EEP stellar track files and \(\texttt{*_isochrones.zip}\) files contain theoretical isochrone files, both in the same format as EEP track and theoretical isochrones found on the MIST website. Zip files labeled, e.g.,\(\texttt{*_isochrones_FILTERSET.zip}\) contain observable isochrones, with synthetic photometry produced for a particular filter set (as on the MIST packaged grids site, which contains more information on the filter sets), computed without extinction (\(A_V=0\)). At the moment, filter sets for \(\texttt{UBVRIplus}\) (containing Gaia filters), \(\texttt{HST_WFC3}\), \(\texttt{HST_ACSWF}\), \(\texttt{HST_WFPC2}\), and \(\texttt{CFHTugriz}\) are included, but more can be added upon request\(^2\). Notes: \(^1\) These are the same models as featured in Gossage et al. 2018, but in that work, [Fe/H] = -0.60 and -0.75 were featured as well and only included models up to v/vcrit = 0.6. We include these models from Gossage et al. 2018 here as well. Models at [Fe/H] = -0.60 have been extended to v/vcrit = 0.9, while [Fe/H] = -0.75 only includes up to the original v/vcrit = 0.6. \(^2\) These tracks and isochrones may be converted into observable tracks and isochrones (w/ gravity darkening effects if desired) via Aaron Dotter's iso code. \(^3\) Although astroseismic \(\nu_{max}\) and \(\Delta \nu\) are included in the included history files, be aware that these are based on scaling relations reliant on solar values, assuming the Coriolis and centrifugal forces do not play a role. While an OK assumption for the Sun, this is less applicable models with rapid rotation and their values should not be trusted in such regimes.本数据集包含Gossage等人2019年发表于《旋转与年龄展宽对延长主序星转折区的联合影响》中的理论等时线与等效演化点（EEP, Equivalent Evolutionary Point）恒星轨迹。这些一维恒星演化模型基于MESA r7503版本构建，采用与MIST v1.0（Choi等人2016年研究）一致的物理假设。 相关模型的详细描述见于Gossage等人2018年与2019年的研究^1，其核心参数特征如下： 1. 金属丰度[Fe/H]取值为-0.45、-0.30、-0.15、0.0、0.15、0.30、0.45（采用Asplund等人2009年给出的原太阳丰度Z☉=0.0142）。 2. 旋转速率采用v/v_crit（临界旋转速度比）取值0.0、0.1、0.2、0.3、0.4、0.5、0.6、0.7、0.8、0.9，初始状态设置在零龄主序(ZAMS, Zero-Age Main Sequence)。 3. 恒星质量范围为0.1至8倍太阳质量，质量间隔设置如下： - 当M < 1M☉时，ΔM = 0.05M☉ - 当1M☉ ≤ M < 2M☉时，ΔM = 0.04M☉ - 当2M☉ ≤ M ≤8M☉时，ΔM = 0.2M☉ 所有模型均演化至首次热脉冲阶段。 ## 文件名约定 压缩包示例如`MIST_v1.0_feh_p0.15_rotating_tracks.zip`，包含特定金属丰度（本例中为[Fe/H]=0.15）下所有旋转速率与质量的理论模型。`MIST_v1.0_feh_m0.15_rotating_tracks.zip`则对应[Fe/H]=-0.15的模型，以此类推。 其中`*_tracks.zip`包含等效演化点（EEP）恒星轨迹文件，`*_isochrones.zip`包含理论等时线文件，格式与MIST网站上的EEP轨迹及理论等时线一致。 带有`*_isochrones_FILTERSET.zip`标签的压缩包包含可观测等时线，其合成测光基于特定滤光片系统（详见MIST网格打包网站，该网站提供更多滤光片系统相关信息），且未考虑V波段消光（A_V=0）。目前已包含的滤光片系统有`UBVRIplus`（包含盖亚滤光片）、`HST_WFC3`、`HST_ACSWF`、`HST_WFPC2`以及`CFHTugriz`，用户也可按需申请添加其他滤光片系统^2。 ## 注释 ^1 本数据集的模型与Gossage等人2018年研究中的模型一致，但该研究额外包含了[Fe/H]=-0.60与-0.75的金属丰度模型，且仅提供了v/v_crit≤0.6的旋转速率模型。本数据集同样包含Gossage等人2018年的这些模型：其中[Fe/H]=-0.60的模型已扩展至v/v_crit=0.9，而[Fe/H]=-0.75的模型仍保留原始的v/v_crit≤0.6的范围。 ^2 这些轨迹与等时线可通过Aaron Dotter开发的iso代码转换为可观测轨迹与等时线（若需要，可加入引力变暗效应）。 ^3 尽管提供的历史文件中已包含星震学ν_max与Δν参数，但需注意这些参数基于依赖太阳参数的标度关系，且假设科里奥利力与离心力无影响。该假设在太阳条件下尚且合理，但对于快速旋转的模型适用性较差，因此在快速旋转情形下不应采信这些参数的数值。