New Sample of Ultracool Dwarf Benchmarks with Detailed Chemical Characterization

Abstract

Ultracool dwarfs (UCDs) are considered prime targets for galactic archeology due to their abundance, long lifespans, and the sensitivity of their spectra to chemical composition. To calibrate larger surveys, a sample of benchmark UCDs with robust abundances is necessary. We present [Fe/H], [α/Fe] and abundances of 13 elements, inferred from high-resolution spectra of 13 FGK primaries hosting a UCD companion. For a subset of our sample with APOGEE observations, individual abundances agree within 0.06 dex on average.