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

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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.