Two-neutron transfer reactions induced by the Borromean nucleus ${}^6\mathrm{He}$ on ${}^4\mathrm{He}$ and ${}^1\mathrm{H}$ targets are analyzed within a realistic four-body model. Available experimental data are well described, and it is the “di-neutron” configuration of the ${}^6\mathrm{He}$ nucleus that is found to make the dominant contribution to the cross sections of the two-neutron transfer reactions.

• Received 18 December 1998

DOI:https://doi.org/10.1103/PhysRevLett.82.4996