finding emission lines (and other oddities) in hot stars

I showed my robust spectral decomposition (dimensionality reduction) and residuals to the MPIA Binaries group today. There was much useful feedback (including that my H-gamma was actually H-delta; embarassing!). One comment was that the model isn't truly a causal separation between star and lines, so there will be some mean lines in the star model; lines aren't entirely outliers. That's true! The…