Two-neutron transfer in nuclei close to the drip line

We investigate the two-neutron transfer modes induced by (t,p) reactions in neutron-rich oxygen isotopes. The nuclear response to the pair transfer is calculated in the framework of continuum quasiparticle random phase approximation (cQRPA). The cQRPA allows a consistent determination of the residual interaction and an exact treatment of the continuum coupling. The (t,p) cross sections are calculated within the distorted wave Born approximation approach and the form factors are evaluated by different methods: macroscopically, following the Bayman and Kallio method, and fully microscopically. A significant part of the cross section corresponds to a high-lying collective mode built entirely upon continuum quasiparticle states.