Stellar Multiplicity Statistics in APOGEE

Stellar multiplicity affects nearly every area of astrophysics, and yet there remain many open questions about the statistics of multiplicity and their relation to fundamental stellar parameters. Fortunately, the APOGEE survey has produced large numbers of publicly-available, high-resolution spectral data and sparsely-sampled radial velocity curves, with which we can investigate relationships between the frequency of close-period companions and stellar parameters. I will present our discovery and characterization of a strong anti-correlation between alpha abundances and the close binary fraction, as well as discuss its implications for star formation. I will also explain how previously discovered trends between the close binary fraction and stellar evolution now inform our understanding of tidal interactions between the two companions.