Massive stars in the Milky Way

Our approach yields a completeness of ~80% and a purity ranging from 0.51+/-0.02 for probabilities between 0.6 and 0.7, up to 0.85+/-0.05 for the 0.9-1.0 range. To externally validate our methodology, we searched for and analyzed archival spectra of moderate- to high-probability (p>0.6) candidates that are not contained in our catalog of labels. Our independent spectral validation confirms the expected performance of the BRF, spectroscopically classifying 300 stars as B3 or earlier (due to observational constraints imposed on the B0-3 range), including 107 new stars.

Based on the most conservative yields of our methodology, our candidate list could increase the number of bright massive stars by ~50%. As a byproduct, we developed an automatic methodology for spectral typing optimized for LAMOST spectra, based on line detection and characterization that guides a decision path.