标题： 星际介质中的磷 显示英文标题

标题： Phosphorus in the Diffuse Interstellar Medium

摘要： 我们展示了通过FUSE和HST/STIS对银河系恒星方向的磷(P) II列密度的测量结果。 我们通过对未饱和的$\lambda$1125 和$\lambda$1533 线进行轮廓拟合来分析P II，并推导出沿视线方向以及各个解析成分中的列密度。 我们发现磷并未在这几个采样弥漫中性气体的方向上发生耗尽。 我们还研究了P II与O I列密度之间的相关性，并发现这两种物种之间不存在差异性耗尽。 此外，N(PII)/N(OI)的比例与太阳的P/O值一致，表明PII和OI共存于同一气相中，并且自它们在恒星中产生以来可能一直同步演化。 我们认为，作为PII追踪的磷，在各种物理环境中都是一个极好的中性氧示踪剂，除非电离修正成为一个显著问题。 因此，PII谱线（可通过FUSE、HST/STIS观测，或通过VLT/UVES观测QSO视线）在OI谱线饱和或混合时尤其适合作为其替代物。 显示英文摘要

摘要： We present FUSE and HST/STIS measurements of the PII column density toward Galactic stars. We analyzed PII through the profile fitting of the unsaturated $\lambda$1125 and $\lambda$1533 lines and derived column densities integrated along the sightlines as well as in individual resolved components. We find that phosphorus is not depleted along those sightlines sampling the diffuse neutral gas. We also investigate the correlation existing between PII and OI column densities and find that there is no differential depletion between these two specie. Furthermore, the ratio N(PII)/N(OI) is consistent with the solar P/O value, implying that PII and OI coexist in the same gaseous phase and are likely to evolve in parallel since the time they are produced in stars. We argue that phosphorus, as traced by PII, is an excellent neutral oxygen tracer in various physical environments, except when ionization corrections are a significant issue. Hence, PII lines (observable with FUSE, HST/STIS, or with VLT/UVES for the QSO sightlines) reveal particularly useful as a proxy for OI lines when these are saturated or blended.