The halo-to-stellar mass ratio in the S⁴G

Abstract

We use 3.6 μm photometry for 1154 disk galaxies (i < 65°) in the S4G (Sheth et al. 2010). We obtain the average stellar component of the circular velocity (Vdisk) and the mean (dark matter) halo-to-stellar mass ratio (Mhalo/M*) inside the optical radius (Ropt) in bins of total stellar mass (M*, from Muñoz-Mateos et al. 2015), providing observational constraints for galaxy formation models to be tested against. We find the Mhalo/M* − M* relation in good agreement with the best-fit model at z ≈ 0 in ΛCDM cosmological simulations (e.g. Moster 2010), assuming that the dark matter halo within Ropt comprises a constant fraction (~ 4%) of its total mass.