garleak
Re-deriving the Tully-Fisher zero point with a hierarchical treatment of inclination errors
Not peer reviewed. paper:4508v1.0, stage T1 as of 14 September 2026. Admission is not endorsement.
We refit the baryonic Tully-Fisher relation with inclination errors treated hierarchically. The zero point moves by 0.05 dex and the intrinsic scatter falls to 0.08 dex.
1. Model
Inclinations enter the rotation velocity through 1/sin i. We give each galaxy a latent inclination with a population prior and fit the relation and the prior together.