Scattering Phase Shifts of Lithium Isotopes

Abstract

Investigation of few body cluster systems is very important in nuclear physics. Problems appearing in few body systems can in principle be divided into two classes: bound state problems and scattering problems. The bound state problems are usually related to the spectroscopy of such systems while scattering problems describe their reactions. The main focus in the work is the scattering problem for systems consisting of two cluster systems. The single channel two body scattering problem is considered in the framework of different spin parity states for lithium isotopes.Scattering phase shifts on negative and positive parity states of 5 Li, 6 Li and 7 Li nuclei are calculated applying two-body 𝛼𝛼𝛼𝛼 + 𝑝𝑝𝑝𝑝, 𝛼𝛼𝛼𝛼 + 𝑑𝑑𝑑𝑑 and 𝛼𝛼𝛼𝛼 + 𝑡𝑡𝑡𝑡 systems and the complex scaling method. 6 Li and 7 Li are stable nuclei and their ground and low-lying excited states are considered in this work.In this study, we calculated scattering phase shifts of the negative parity 𝐽𝐽𝐽𝐽 𝜋𝜋𝜋𝜋 = 3/2 − and 𝐽𝐽𝐽𝐽 𝜋𝜋𝜋𝜋 = 1/2 − states for 𝑝𝑝𝑝𝑝 −wave of 5 Li, 𝐽𝐽𝐽𝐽 𝜋𝜋𝜋𝜋 = 7/2 − , 5/2 − , 3/2 − and 1/2 − states for 𝑝𝑝𝑝𝑝 − and 𝑓𝑓𝑓𝑓 −waves of 7 Li and the positive parity 𝐽𝐽𝐽𝐽 𝜋𝜋𝜋𝜋 = 1 + , 2 + , 3 + states for 𝑠𝑠𝑠𝑠 − and 𝑑𝑑𝑑𝑑 − waves of 6 Li.