Collaborative Research: Adding a Magnetic Dimension to M-dwarf Stars Observed by APOGEE

到目前为止，M矮星是银河系中数量最多的恒星类型，它们代表着一个重要的系外行星宿主家族。此外，它们的寿命超过了银河系本身的年龄，因此对M-矮星的大样本进行详细的化学丰度研究将对银河系历史产生重要的见解。这个团队将测量约30,000颗M矮星的磁场强度，这些M-矮星是阿帕奇点天文台星系演化实验调查的一部分。他们将作为导师参与斯隆基金会的教师和学生团队(FAST)倡议，该倡议针对美国机构的教师和学生，这些机构在为代表不足的少数族裔学生提供服务方面有着丰富的历史。来自这些机构的教师/学生团队与斯隆数字天空调查的现有合作伙伴或合作者相匹配。在高分辨率下观测到的1.5-1.7微米之间的远地点光谱区域，包含了关于M矮星的重要诊断信息，例如详细的化学丰度模式，以及通过塞曼分裂或塞曼增强线探测恒星磁场的可能性。该团队将开发必要的技术来获得准确的恒星参数(有效温度和表面引力)，以及详细的化学丰度，同时在分析中包括磁塞曼分裂。这将导致在远地点调查中增加M-矮星的磁活动维度，对有效温度、金属丰度和年龄范围广泛的M-矮星进行抽样，并包括大量寄存在系外行星上的M-矮星。这一对M矮星群体的更全面的看法将在总体上促进冷星天体物理学的广泛领域的知识和理解，同时也提供关于系外行星托管的M矮星样本中的恒星磁场的知识。这一奖项反映了美国国家科学基金会的法定任务，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

M-dwarf stars are, by far, the most numerous type of star in the Milky Way, and they represent an important family of exoplanet hosts. In addition, their lifetimes exceed the age of the Galaxy itself, so detailed chemical abundance studies of large samples of M-dwarfs will yield important insights into Galactic history. This team will measure magnetic field strengths in a sample of ~30,000 M-dwarfs that have been observed as part of the APOGEE (Apache Point Observatory Galactic Evolution Experiment) survey. They will participate as mentors in the Sloan Foundation's Faculty and Student Team (FaST) initiative, which targets faculty and students at U.S. institutions with strong histories in serving underrepresented minority students. Faculty/student teams from these institutions are matched to established Sloan Digital Sky Survey partners or collaborators. The APOGEE spectral region, between 1.5 - 1.7 microns, observed at high resolution, contains significant diagnostic information for M-dwarfs, such as detailed chemical abundance patterns, as well as the possibility to detect stellar magnetic fields via Zeeman split or Zeeman enhanced lines. This team will develop the techniques necessary to derive accurate stellar parameters (effective temperatures and surface gravities), as well as detailed chemical abundances, while including magnetic Zeeman splitting in the analysis. This will result in the addition of a magnetic activity dimension for the M-dwarfs in the APOGEE survey, sampling a population of M-dwarfs covering a broad range in effective temperatures, metallicities and ages, and including a large number of exoplanet-hosting M-dwarfs. This more encompassing view of the M-dwarf population will advance knowledge and understanding across the broad field of cool-star astrophysics, in general, while also providing knowledge about stellar magnetic fields in a sample of exoplanet-hosting M-dwarfs.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.