Charge Radius And Neutron Skin Thickness Of Platinum And Osmium Isotopes Near The Nuclear Drip Lines

Abstract
Background: The density distributions of exotic nuclei are different from that of stable nuclei. For stable nuclei, charge radii can be obtained through electron scattering experiments. The excessive neutrons in neutron-rich nuclei make a decoupling of neutron and proton distribution and as a result nuclear skin structures are appeared. Purpose: The charge radius and the way by which nucleons are distributed can provide information about size, surface thickness and shell structure of nuclei. The information collected from such nuclei can be used for astrophysical studies to understand the origin of heavy elements. Methods: In the present study, we have made an attempt to investigate the charge radii, rms radii and skin thickness of Pt and Os isotopes. Here, the calculations were made by using the HFB solver which utilizes HO single-particle basis and iteratively diagonalizes the HFB Hamiltonian based on the Skyrme forces. Results: Here we can observe an increase in charge radius, rms radius and skin thickness with neutron number. The charge radii calculated are in good agreement with the experimental data and predictions of RCHB model. A linear dependence of skin thickness on neutron number is observed with the change in slope is noticed around N =126. Conclusion: Using HFB theory, we have analyzed the charge radius and neutron skin thickness of Pt and Os isotopes. The drip line nuclei have larger charge radius in comparison to the stable nuclei. The redistribution of the nucleons due to addition of neutrons leads to the gradual increase in neutron skin. The sudden increase of skin thickness may be due to the extra stability and shell closure around the magic number.