Dark matter in NGC 4636

We derive constraints on the dark matter distribution in the elliptical galaxy NGC 4636 using the spatially resolved temperature profile from the ASCA SIS. We find that NGC 4636 becomes dark matter dominated at roughly the de Vaucouleurs radius; and the ratios of total integrated mass to light and local nonbaryonic to baryonic matter increase monotonically outward, attaining values of ≊150 M⊙/LB⊙ and ∼80, respectively, at 100 kpc.