Evidence for major mergers of galaxies at 2 less than or similar to z < 4 in the VVDS and VUDS surveys

Context. The mass assembly of galaxies can proceed through different physical processes. Here we report on the spectroscopic identification of close physical pairs of galaxies at redshifts 2 less than or similar to z < 4 and discuss the impact of major mergers in building galaxies at these early cosmological times. Aims. We aim to identify and characterize close physical pairs of galaxies destined to merge and use their properties to infer the contribution of merging processes to the early mass assembly of galaxies. Methods. We searched for galaxy pairs with a transverse separation r(p)