One- and two- neutron halo at the dripline. From $^{11}$Be to $^{11}$Li and back: $^{10}$Li and parity inversion

The nuclei $^{11}$Be and $^{11}$Li provide paradigmatic examples of one-and two- neutron halo systems. Because the reaction $^{1}$H($^{11}$Li,$^{9}$Li)$^{3}$H is dominated by successive transfer, one can use the quantitative picture emerging from a nu- clear field theory description of the structure and reaction mechanism of the above Cooper pair transfer process and of the $^{2}$H($^{10}$Be,$^{11}$Be)$^{1}$H and $^{1}$H($^{11}$Be,$^{10}$Be)$^{2}$H reactions, to shed light on the structure of $^{10}$Li. This analysis provides important support for a parity inverted scenario with a 1/2$^{+}$ virtual state at about 0.2 MeV.