Unified description of $^6$Li structure and deuterium-$^4$He dynamics with chiral two- and three-nucleon forces

G. Hupin (1) , S. Quaglioni (1) , P. Navrátil (2)

1 LLNL - Lawrence Livermore National Laboratory
2 TRIUMF [Vancouver]

We provide a unified ab initio description of the Li6 ground state and elastic scattering of deuterium (d) on He4 (α) using two- and three-nucleon forces from chiral effective field theory. We analyze the influence of the three-nucleon force and reveal the role of continuum degrees of freedom in shaping the low-lying spectrum of Li6. The calculation reproduces the empirical binding energy of Li6, yielding an asymptotic D- to S-state ratio of the Li6 wave function in the d+α configuration of −0.027, in agreement with a determination from Li6−He4 elastic scattering, but overestimates the excitation energy of the 3+ state by 350 keV. The bulk of the computed differential cross section is in good agreement with data. These results endorse the application of the present approach to the evaluation of the H2(α,γ)Li6 radiative capture, responsible for the big-bang nucleosynthesis of Li6.

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

G. Hupin, S. Quaglioni, P. Navrátil. Unified description of $^6$Li structure and deuterium-$^4$He dynamics with chiral two- and three-nucleon forces. Physical Review Letters, 2015, 114 (21), pp.212502. ⟨10.1103/PhysRevLett.114.212502⟩. ⟨hal-04346173⟩