Using Old and New Approaches: Determining Luminosities of Brown Dwarfs with Spectral Type Polynomials and Machine Learning

Using the first volume-limited sample of several hundred brown dwarfs (Best et al., submitted) defined entirely by parallaxes, we provide an update to the absolute magnitudes as a function of spectral types L0-T8 in 14 bands spanning Pan-STARRS g to WISE W3. These include the first relations for brown dwarfs using Pan-STARRS1 photometry. These fits are analyzed and compared to previous empirical relations. Slight differences are noted in MKO and 2MASS photometry. We also investigate applications of machine learning models to directly infer luminosities and other physical properties, such as effective temperature and chemical abundances, of brown dwarfs from their photometry and spectra.