VIPERS: Probing the growth of structure at z~1

Abstract

In galaxy redshift surveys, the line-of-sight velocity information is encoded in the observed redshift as a Doppler component that radially distorts the galaxy positions. The linear component of such `Redshift-Space Distortions' (RSD) is directly proportional to the growth rate of structure, f(z), and motivates the interest in RSD as a powerful way to constrain gravity. However, the non-linear evolution of the density and velocity fields requires the use of sophisticated theoretical models to extract reliable cosmological information from quasi-linear scales. Alternatively, one can use tracers of the LSS less sensitive to the non-linear motions at small scales. After an overview of VIPERS I will present a novel method that uses the clustering of luminous blue galaxies to obtain an accurate estimate of the growth rate while keeping the theoretical model relatively simple.