发表机构
Keele University; Pontificia Universidad Católica de Chile; European Southern Observatory（基尔大学; 智利天主教 Pontificia 大学; 欧洲南方天文台）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究以5颗带M型矮星伴星的类太阳食双星为对象，利用TESS光变曲线及NIRPS、HARPS光谱获取精确恒星参数，提供新恒星基准并深化对M型矮星的认知。
AI 中文摘要
大规模光谱巡天需要合适的基准恒星来验证自动处理流程的性能，而包含FG型星与低温伴星的分离式食双星（DEB）是颇具潜力的一类候选天体。当通量比≤1%时，该双星系统的光谱几乎与单星无异；由于获取双星精确参数的方法已成熟，这类天体将成为优秀的基准候选体。我们利用TESS光变曲线，以及欧洲南方天文台（ESO）3.6米望远镜上NIRPS和HARPS的高分辨率光谱，分析了一组带有M型矮星伴星的DEB，获取了恒星组分的精确基本参数；通过互相关可探测到次级组分，使其也能得到表征。结合分析得到的恒星参数，我们可利用盖亚（Gaia）视差和存档星等数据测量精确的有效温度，还能从恒星光谱中提取主星的化学组成。本次分析中，次级组分对测得的光谱参数影响极小；我们测得的半径和质量精度优于0.1%，主星有效温度精度也极高。除提供新一批恒星基准外，本研究分析的次级组分还构成了表征充分的M型矮星样本，将有助于深化对低质量恒星结构与演化的理解。
英文摘要
Large-scale spectroscopic surveys will need suitable benchmark stars that can be used to verify the performance of automatic pipelines. A promising type of object for this purpose is the detached eclipsing binary (DEB) containing an FG-star and a low temperature companion. For flux ratios $\lesssim1$~per~cent, the spectra obtained for the binary will be almost identical to a single star. As the methods for obtaining accurate parameters for binaries are well established, they would be excellent benchmark candidates. We analyse a group of DEBs with M-dwarf companions using TESS light curves and high resolution spectroscopy from NIRPS and HARPS on the ESO 3.6-m telescope. We obtain accurate fundamental parameters for the stellar components. The secondary component is visible with cross-correlation, allowing them to be characterised as well. With the stellar parameters obtained from the analysis, we can measure precise effective temperatures from Gaia parallaxes and archival magnitude data. Chemical compositions of the primary stars are also extracted from the stellar spectra. In this analysis, the secondary components have minimal impact on determined spectroscopic parameters. Our radii and masses are characterised to within sub per~cent precision as well as our primary effective temperatures. Beyond a new set of stellar benchmarks, the secondary components analysed in this work represent a well characterised sample of M-dwarf stars which will be useful to improve our understanding of low mass structure and evolution.
Comments17 pages, 13 figures, Accepted for publication in MNRAS
