  We present a theoretical framework for treating the full excitation spectrum
of J{\pi} = 0+ pair addition modes, including the well-known low-lying and
bound Pairing Vibration on par with the predicted Giant Pairing Vibration lying
in the continuum. Our formalism includes the coupling to low-energy collective
quadrupole modes of the core, in such a way that both single-particle
self-energy effects and the pairing interaction induced by phonon exchange are
accounted for. The theory is applied to the case of the excitation spectrum of
14C, recently populated by two-neutron transfer reactions.
