M dwarfs are the most common type of star in the Galaxy , and because of their small size are favored targets for searches of Earth-sized transiting exoplanets .
Current and upcoming all-sky spectroscopic surveys , such as the Large Sky Area Multi-Object Fiber Spectroscopic Telescope ( LAMOST ) , offer an opportunity to systematically determine physical properties of many more M dwarfs than has been previously possible .
Here we present new effective temperatures , radii , masses , and luminosities for 29,678 M dwarfs with spectral types M0—M6 in the first data release ( DR1 ) of LAMOST .
We derived these parameters from the supervised machine learning code , The Cannon , trained with 1,388 M dwarfs in the Transiting Exoplanet Survey Satellite ( TESS ) Cool Dwarf Catalog that were also present in LAMOST with high signal-to-noise ratio ( > 250 ) spectra .
Our validation tests show that the output parameter uncertainties are strongly correlated with the signal-to-noise of the LAMOST spectra , and we achieve typical uncertainties of 110 K in T _ { eff } ( \sim 3 % ) , 0.065 R _ { \odot } ( \sim 14 % ) in radius , 0.054 M _ { \odot } ( \sim 12 % ) in mass , and 0.012 L _ { \odot } ( \sim 20 % ) in luminosity .
The model presented here can be rapidly applied to future LAMOST data releases , significantly extending the samples of well characterized M dwarfs across the sky using new and exclusively data-based modeling methods .