Pairing correlations and two-nucleon transfer between heavy nuclei

The focus of this paper is the use of heavy-ion induced two-nucleon transfer reactions to probe pairing correlations in heavy nuclei. The discussion is restricted to reactions at the Coulomb barrier where quasi-elastic reactions dominate which simplifies the problem both theoretically and experimentally. It is shown that recent technical advances are making it feasible to exploit the unique features of heavy-ion induced transfer reactions to probe nuclear structure. Recent results bode well for rapid advances in the study of pairing correlations to high spin and the search for nuclear analogs of solid-state pairing phenomena, the Holy Grail of this field. The article concludes with a summary of the outlook for further development of heavy-ion induced transfer reactions and the outstanding scientific opportunities they will provide for probing nuclear structure. (orig./HSI)