The Sloan Digital Sky Survey (SDSS) has been mapping the sky for almost a decade, providing crucial information on the dark universe though measurements of BAO and RSD (redshift space distortions). As one of the SDSS components, the Lyman-alpha forest survey is a rich source of information. Because it gives access to small (tens of Mpc) scales, it allows one to probe the impact on the clustering of matter of neutrino mass and warm dark matter. I will briefly recall the major goals of SDSS, and introduce the quasar survey where the Lyman-alpha forest is measured. I will then present one of the strongest constraints on neutrino mass from a combination of CMB and Lyman-alpha data. Finally, I will show how the study of clustering in the Lyman-alpha forest can also lead to competitive constraints on warm dark matter and on several models of keV sterile neutrinos.
Organizer: V. Lebouteiller, local contact: D. Elbaz