Two-neutron correlations in 6He in a Coulomb breakup reaction

摘要

We investigate the three-body Coulomb breakup of a two-neutron halo nucleus, 6He. Based on the α + n + nnmodel, the three-body scattering states of 6He are described by using the combined methods of the complexnscaling and the Lippmann-Schwinger equation. We calculate the breakup cross section, the two-dimensionalnenergy distributions, and the invariant mass spectra for the E1 transition of 6He.We discuss the relations betweennthe structures in these strengths and the n-n and α-n correlations of 6He. It is found that the 5He resonance innthe final states contributes to make a low-energy enhancement of the strength. The n-n final-state interaction alsoncontributes to enhance the strength globally. However, the ground-state correlations of 6He, such as a dineutron,nare difficult to recognize in the strength because of the dominant effect of the final-state interaction