AI 中文总结
本文提出一种新的多基组方法，将准H₂⁺共振引入线型计算，实现于线型代码后发现新线型与氢大气白矮星观测光谱吻合更好。
AI 中文摘要
理论光谱线型描述了热稠密等离子体中束缚电子跃迁导致的不透明度分布，用于拟合众多天体物理源的出射光谱。线展宽理论的不足被认为是白矮星大气及白矮星光球条件实验室实验中理论与观测光谱未解决差异的可能解释之一，差异的一个可能来源是准分子的形成。准分子是原子间的近距离（未束缚）碰撞，会展宽线型并产生额外伴线，准分子难以在传统线型代码中实现，历史上需采用超出标准斯塔克展宽模型的多个物理近似。本文提出一种计算含准分子共振的线型的新方法，采用同时考虑原子与分子态的新型多基组方法，将该方法实现到模拟线型代码中，给出含准H₂⁺共振的氢莱曼系线型，并展示新线型对氢大气白矮星模型光谱的影响。研究发现，新方法得到的准分子特征更宽，与初始对比中的观测光谱吻合良好。
英文摘要
Theoretical spectral line shapes describe the distribution of opacity due to bound electronic transitions in hot dense plasmas and are used to fit emergent spectra from many astrophysical sources. Deficiencies in line broadening theory have been proposed as a possible explanation for unresolved discrepancies between theoretical and observed spectra in white dwarf star atmospheres and laboratory experiments at white dwarf star photosphere conditions. One possible source of these discrepancies is the formation of quasi-molecules. Quasi-molecules are close (unbound) collisions between atoms, which broaden line shapes and create additional satellite lines. Quasi-molecules are challenging to implement into traditional line shape codes and have historically required a number of physical approximations beyond what is used in standard Stark broadening models. Here we present a new approach to calculating line shapes with quasi-molecular resonances, using a novel multiple-basis method that considers both atomic and molecular states. We implement this approach into a simulation line shape code, present hydrogen Lyman-series line shapes with quasi-H$_2^+$ resonances, and demonstrate the impact our new line shapes have on hydrogen-atmosphere white dwarf star model spectra. We find that our new approach leads to broader quasi-molecular features that agree well with observed spectra in initial comparisons.
Comments20 pages, 15 figures, accepted by ApJ
