Quantifying maximum discs in galaxies

The precise definition of this term, however, can be vague and varies in usage. We develop an algorithm to robustly quantify maximum-disc mass models and apply it to 153 galaxies from the Spitzer Photometry and Accurate Rotation Curve data base.

Our automatic procedure recovers classic results from manual decompositions. High-mass, high-surface-brightness galaxies have mean maximum-disc mass-to-light ratios of ~0.7M_{sun}_/L_{sun}_ in the Spitzer 3.6{mu}m band, which are close to the expectations from stellar population models, suggesting that these galaxies are nearly maximal. Low-mass, low-surface-brightness galaxies have very high maximum-disc mass-to-light ratios (up to 10M_{sun}_/L_{sun}_), which are unphysical for standard stellar population models, confirming they are sub-maximal.