Unsurprising Aspects of Heavy-Ion-Induced Two-Nucleon Transfer Reactions

An apparent puzzle concerning the suppression of heavy-ion-induced $\mathrm{nn}$ and $\mathrm{pp}$ transfers compared to $\mathrm{np}$ transfer in light nuclei can be explained to a great extent by invoking simple arguments based on the binding energies of the transferred pairs to the two cores. The manifestation of this effect is in the tail regions of the appropriate bound-state wave functions where transfer is well known to occur. These arguments may be extended to include multinucleon transfers where the consequences of this effect could be even more drastic.