An Effective Field Theory Description Of The Halo Nucleus ³¹Ne

Halo nuclei are widely widespread in the vicinity of drip line.Due to the inherent characteristics of rich protons or neutrons,those nuclei have the property of weak binding which are inconsistent with common nuclei.Many methods have been applied to describe those nuclei,one of the most successful method is Halo Effective Field Theory?Halo EFT?.Halo EFT has been used in many nuclei(such as⁶He,⁸B,¹¹Be,¹¹Li,¹⁹C)for calculating the quantities like charged radius and one neutron separation energy,and the results are consistent with the experimental data.Based on the effective field theory of halo nuclei,a dimensionless parameter repre-senting the degree of halo structure of³¹Ne is calculated.Our results show that the nu-cleus has a neutron halo structure and its core is a deformable nucleus.Then the charge radius of³¹Ne ground state is calculated and the scattering volume and oneneutron sepa-ration energy are given.The results show that the effective field theory of halo nucleus is harmony with the experiment.So far,this is the only work that can theoretically explain the ground state separation energy of³¹Ne ground state.Finally,we use this method to caculate the neutron separation energy of³¹Ne?fifth?excited state.