论文标题
线力乘数参数的演变在辐射驱动的巨星风中
Evolution of Line-Force Multiplier Parameters in Radiation Driven Winds of Massive Stars
论文作者
论文摘要
我们提出了两个自洽的程序，将流体动力学与辐射风理论框架中的线力相结合。这些程序为我们提供了线力参数，速度场和质量损失率。第一个基于所谓的M-CAK理论。介绍了$ T_ \ text {eff} \ ge 32,000 $ k的完整线力参数，表面重力高于3.4 dex，用于两个不同的金属率，以及它们的相应风参数。我们发现，线 - 力参数对有效温度的依赖性通过对$ \ log g $的依赖增强。对于均匀的风（不集结）自洽的质量损失率的比较表明，与经验价值相吻合。我们还考虑自洽的风解决方案，这些溶液被用作快速的输入来计算合成光谱。通过与观测到的三颗恒星的光谱相比，我们发现合成光谱迅速收敛到溶液的邻域区域。因此，这种自洽的M-CAK程序大大减少了获得合成频谱所需的自由参数的数量。 第二个程序（称为Lambert-Procedure）提供了超出M-CAK理论的自洽解决方案，并且线加速器由完整的NLTE辐射传输代码CMFGEN计算。质量损失速率和结块因子都设置为自由参数，因此在计算各自的自洽水动力学之后，通过光谱拟合获得了它们的值。由于执行Lambert-Procedure需要显着的计算能力，因此仅针对星Z-Puppis进行分析。 有希望的结果为本文提出的自洽解决方案的未来应用提供了积极的平衡。
We present two self-consistent procedures that couple the hydrodynamics with calculations of the line-force in the frame of radiation wind theory. These procedures give us the line-force parameters, the velocity field, and the mass-loss rate. The first one is based on the so-called m-CAK theory. A full set of line-force parameters for $T_\text{eff}\ge 32,000$ K and surface gravities higher than 3.4 dex for two different metallicities are presented, along with their corresponding wind parameters. We find that the dependence of line-force parameters on effective temperature is enhanced by the dependence on $\log g$. For the case of homogeneous winds (without clumping) comparison of self-consistent mass-loss rates shows a good agreement with empirical values. We also consider self-consistent wind solutions that are used as input in FASTWIND to calculate synthetic spectra. By comparison with the observed spectra for three stars with clumped winds, we found that varying the clumping factor the synthetic spectra rapidly converge into the neighbourhood region of the solution. Therefore, this self-consistent m-CAK procedure significantly reduces the number of free parameters needed to obtain a synthetic spectrum. The second procedure (called Lambert-procedure) provides a self-consistent solution beyond m-CAK theory, and line-acceleration is calculated by the full NLTE radiative transfer code CMFGEN. Both the mass-loss rate and the clumping factor are set as free parameters, hence their values are obtained by spectral fitting after the respective self-consistent hydrodynamics is calculated. Since performing the Lambert-procedure requires significant computational power, the analysis is made only for the star z-Puppis. The promising results gives a positive balance about the future applications for the self-consistent solutions presented on this thesis.
