银河系磷巡天。I. 来自约750颗FGK恒星的银盘化学演化
The Galactic Phosphorus Survey. I. Chemical Evolution across the Galactic Disk from $\sim$750 FGK Stars
- The University of Texas at Austin（德克萨斯大学奥斯汀分校）
- Indiana University（印第安纳大学）
- Ege University（埃格大学）
- Louisiana State University（路易斯安那州立大学）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本研究利用约750颗FGK恒星的高分辨率近红外光谱，均匀测量磷丰度，揭示[P/Fe]随金属丰度降低而升高并在约-1.0 dex处达峰，厚盘较薄盘富磷约0.08 dex，并测得径向和垂直梯度，为银河系化学演化模型提供新基准。
AI中文摘要：
磷（P）是一种奇Z元素，主要在大质量恒星中产生，同时作为生命必需元素，对行星化学也至关重要。然而，由于精确且均匀的恒星磷测量数据稀缺，其在宇宙时间尺度上的演化至今仍缺乏约束。我们利用迄今最大规模的均匀分析样本——包含约750颗具有高分辨率近红外光谱的FGK恒星——确定了银盘不同金属丰度范围内[P/Fe]与[Fe/H]的关系，并评估了不同恒星族群间的差异。恒星参数通过光谱-测光联合方法确定，磷丰度通过将合成光谱拟合至P I 10529.52 Å吸收特征得出。我们确认[P/Fe]随金属丰度降低而升高，直至[Fe/H]约-1.0 dex处达到峰值，其趋势与同一金属丰度范围内α元素丰度比的上升大致相似，支持大质量恒星在短时标核坍缩超新星过程中的主导贡献。将样本按银盘族群划分后，在固定金属丰度下，厚盘恒星的[P/Fe]系统性高于薄盘约0.08 dex。我们还测量了径向[P/Fe]梯度为-0.124 ± 0.006 dex kpc⁻¹，垂直梯度为+0.052 ± 0.007 dex kpc⁻¹。尽管当前的化学演化模型难以重现观测到的趋势，本巡天将均匀测量的恒星磷丰度数量增加了约三倍，为银河系化学演化模型及行星系统可用的磷储量提供了新的基准。
英文摘要：
Phosphorus (P) is an odd-$Z$ element produced primarily in massive stars and is also important for planetary chemistry as an element essential to life. However, its evolution over cosmic time remains poorly constrained because precise and homogeneous stellar P measurements are scarce. We determine the relationship between [P/Fe] and [Fe/H] over a range of metallicities across the Galactic disk and assess its variation between different stellar populations using the largest uniformly analyzed sample to date, comprising $\sim$750 FGK stars with high-resolution near-infrared spectra. Stellar parameters are determined through a spectro-photometric approach and P abundances are derived by fitting synthetic spectra to the P~I 10529.52~Å absorption feature. We confirm that [P/Fe] increases toward lower metallicities down to [Fe/H] $\sim$ -1.0 dex, where it appears to peak, broadly resembling the rise seen in $α$-element abundance ratios over the same metallicity range and supporting a dominant contribution from massive stars on short core-collapse supernova timescales. When separating the sample into Galactic disk populations, thick-disk stars are systematically enhanced in [P/Fe] relative to the thin disk by $\sim$0.08 dex at fixed metallicity. We also measure a radial [P/Fe] gradient of $-0.124 \pm 0.006$ dex kpc$^{-1}$ and a vertical gradient of $+0.052 \pm 0.007$ dex kpc$^{-1}$. Although current chemical evolution models struggle to reproduce the observed trends, this survey increases the number of homogeneously measured stellar P abundances by approximately a factor of three, providing a new benchmark for Galactic chemical evolution models and the phosphorus inventory available to planetary systems.
