AI 中文总结
研究M矮星Fe I和FeH线铁丰度不匹配问题，通过分析多种恒星光谱，用特定模型和代码推导金属丰度，得出不同星团M矮星金属丰度及相关一致性情况，发现不调整FeH gf值时总体一致性最佳。
AI 中文摘要
最近的研究表明，在M矮星的H波段光谱中，由Fe I和FeH线得出的铁丰度之间存在高达0.20 dex的不匹配。本研究分析了18个由G矮星主星和M矮星伴星组成的双星、4个有测量角直径的M矮星以及毕宿星团和后发星团的6个M矮星成员的近红外H波段APOGEE光谱，以评估FeH线表并检查FeH gf值中可能的系统不确定性。测试使用1-D LTE平面平行模型大气、辐射传输代码和基线APOGEE光谱线表。得出毕宿星团M矮星平均金属丰度为⟨[Fe/H]⟩=+0.08±0.04，后发星团为⟨[Fe/H]⟩=+0.02±0.08。双星系统中G矮星和M矮星的金属丰度一致性良好，开放星团的平均金属丰度也与高分辨率光学分析的文献值一致。研究了光谱和干涉有效温度标度之间的一致性，发现不确定性范围内一致。强制光谱和干涉有效温度标度完全一致会导致双星和开放星团中金属丰度匹配变差。结论是不对基于Hargreaves等人（2010年）线表的FeH gf值进行调整时，总体一致性最佳。
英文摘要
Recent studies have suggested a mismatch of up to 0.20 dex between iron abundances derived from Fe I and FeH lines in the H-band spectra of M dwarfs, and in this work we investigate the nature of this possible offset. We analyze near-infrared H-band APOGEE spectra of stars in 18 binaries composed of a G-dwarf primary and an M-dwarf secondary, together with four M-dwarf stars having measured angular diameters from the literature, and six M-dwarf members of the Hyades and Coma Berenices open clusters. These three families of benchmarks were used to evaluate the FeH line list and check for possible systematic uncertainties in the FeH $gf$-values. Our tests used 1-D LTE plane-parallel model atmospheres, a radiative transfer code, and the baseline APOGEE spectral line list to derive metallicities for the binary G-dwarf primaries using Fe I lines, while stellar parameters and metallicities for the M dwarfs used both FeH and Fe I lines. The mean metallicity obtained for the Hyades M-dwarfs was $\langle$[Fe/H]$\rangle$=+0.08$\pm$0.04, and for Coma Berenices $\langle$[Fe/H]$\rangle$=+0.02$\pm$0.08. The metallicities of the G- and M-dwarfs in binary systems showed excellent agreement (0.06 dex), and the mean metallicities for the open clusters were also consistent with literature values from high-resolution optical analyses. We investigated the consistency between the spectroscopic and interferometric $T_{\rm eff}$ scales, finding agreement within the uncertainties. Forcing full agreement between the spectroscopic and interferometric $T_{\rm eff}$ scales resulted in a poorer match for the metallicities in the binaries and the open clusters. We conclude that the best overall concordance is obtained when no adjustments are made to the FeH $gf$-values, which are based on the Hargreaves et al. (2010) line list.
Comments19 pages, 8 figures and 5 tables
