Star formation and dust obscuration at z ≈ 2

We present preliminary results of a study aimed to constrain the star formation rate and dust content of galaxies as a function of mass at z≈ 2,, a crucial time for galaxy evolution: this is the cosmic epoch when most of the stars in the Universe are formed. We use a sample of star forming galaxies to perform a stacking analysis of their 1.4 GHz radio continuum as a function of different stellar population properties. Dust unbiased star formation rates are retrieved from radio fluxes. The main results of this work are: i) Galaxies in our sample show no downsizing pattern: specific star formation rates are constant over more than 1 dex in mass and up to the highest stellar mass probed; ii) a model independent UV dust attenuation law is provided which can be used to retrieve UV corrected SFR for extensive samples and hence a dust free cosmic star formation rate density