  We study adiabatic pumping through a double quantum dot coupled to normal and
superconducting leads. For this purpose a perturbation expansion in the tunnel
coupling between the dots and the normal leads is performed and processes
underlying the pumping current are discussed. Features of crossed Andreev
reflection are investigated in the average pumped charge and related to local
Andreev reflection in a single quantum dot. In order to distinguish Cooper pair
splitting from quasi-particle pumping, we compare the properties of Cooper pair
pumping with single-electron pumping in a system with only normal leads. The
dependence on the average dot level and the coupling asymmetry turn out to be
the main distinguishing features. This is contrasted with the linear
conductance for which it is more difficult to distinguish single-particle from
Cooper pair transport.
