A First Attempt to Calibrate the Baryonic Tully-Fisher Relation with Gas Dominated Galaxies

Abstract

We calibrate the Baryonic Tully-Fisher (BTF) Relation using a sample of gas dominated galaxies. These determine the absolute scale of the baryonic mass--rotation speed relation independent of the choice of stellar mass estimator. We find a BTF slope of 3.94 +/- 0.07 (random) +/- 0.08 (systematic) and a zero point of 1.79 +/- 0.26 (random) +/- 0.25 (systematic). We apply this relation to estimate the stellar masses of star dominated galaxies. This procedure reproduces the trend of mass-to-light ratio with color predicted by population synthesis models. The normalization is also correct, consistent with empirical estimates of the IMF used in such models.