Properties of Titanium isotopes in complex momentum representation within relativistic mean-field theory

The self-consistent quadruple potential is deduced within the relativistic mean-field(RMF)framework and substituted into the Hamiltonian,which is calculated using the complex momentum representation(CMR).Considering even-even titanium isotopes as an example,this study investigated various properties,including the resonant states of neutron-rich nuclei in the RMF-CMR model,and used them to describe the binding energy.The abrupt decrease in the two-neutron separation energy(S_(2n))corresponds to the traditional magic number.The resonant and bound states are simultaneously exposed in the complex moment plane,where the continuum is along the integration contour.The four oblate neutron-rich nuclei^(72-78)Ti are weakly bound or resonant because their Fermi energies are approximately 0 MeV.The root-meansquare(RMS)radii of these nuclei increase suddenly compared with those of others(neutron number N<48).Moreover,^(78)Ti and^(76)Ti are determined as drip-line nucleons by the value of S_(2n) and the energy levels,respectively.Finally,the weak-bounded character can be represented by diffuse density probability distributions.

Exploring the halo phenomena of medium-mass nuclei having approximately Z=40 with point-coupled parameters in complex momentum representations

To explore the properties of neutron-rich nuclei with approximately 40 protons,the density-dependent point coupling(DD-PC1)effective interaction parameter is adopted in the relativistic mean-field theory with the complex momentum representation(RMF-CMR).The calculated two-neutron separation energy(S_(2n))and root-mean-square(rms)radii support the halo structure that appear in Mo and Ru isotopic chains.Besides,the neutron skin structures appear in Kr and Sr isotopes.The conclusions drawn are also supported by the single-particle energy levels and their occupancy probability and density distribution.Particularly,the energy levels,which reduce to bound states or are approximately 0 MeV with a small orbital angular momentum,are suggested to provide the primary contribution to increasing the neutron radius.Moreover,the single-particle energy levels significantly reflect the shell structure.In addition,the neutron drip line nuclei for Kr,Sr,Mo,and Ru elements are proposed via the changes in S_(2n).