First self-consistent study of 1<i>n</i> halo nucleus ¹⁹C from D-RHFB structure to reaction observables on a beryllium target

Abstract Neutron-rich odd carbon isotopes are the typical candidates possessing novel one-neutron (1 n ) halo structure. For the first time, we employ the axially deformed relativistic Hartree–Fock–Bogoliubov (D-RHFB) model with the effects of the continuum, pairing correlations and tensor force to achieve the 1/2 + ground state (g.s.) supporting 1 n halo of 19 C, which is a long-standing problem for theorists. Taking the structural D-RHFB as the inputs of the Glauber model, we can reproduce the 1 n removal cross sections and the narrow longitudinal momentum distributions of the breakup reaction 19 C + 9 Be at both low-energy region 60, 70 MeV u −1 and high-energy region 700 MeV u −1 , respectively. Furthermore, we clarify the dominant s -wave contribution to 1 n halo from the reaction observables, while the possibility of 3/2 + for g.s. in 19 C has been completely ruled out. Additionally, it is found that the continuum plays a crucial role in the formation of halo nucleus, whereas the tensor force carried by the π -meson coupling does not exert much effect on the halo extension.