Low-x and diffraction measurements at RHIC

RHIC can probe low-x partons in nuclei in p/d+A collisions at forward rapidities, where non-linear QCD effects are expected to set in. So far no clear experimental observation of the onset of gluon saturation has been made. Di-hadron/jet correlations and ratios of hadrons yields in p+p and p/d+A collisions at forward rapidities can be linked to modifications of nuclear parton distributions arising from gluon saturation or gluon shadowing. Furthermore, the long-range ridge-like structure in the di-hadron correlations in p/d+A collisions has also been proposed to be driven by initial state effects like gluon saturation