a. van der Wel on "The IR Properties of Early-Type Galaxies at z=1"

The rest-frame K-band mass-to-light ratio has increased by a factor of three since z=1. The one for B even slightly more. Even though it's are early-type (elliptical) galaxies that are studied, there seems to be 10% of young stars (not sure if I heard that correctly) in the z=1 sample. There is however no obscured SF or contribution from AGN.

Dynamical mass estimates are fine at all redshifts, but if one does SED-fitting in the optical and the IR, the derrived masses are higher by a factor of two to three in the IR, as compared to optical. This has implications in how well we know the global stellar mass density and how it involves