Structure of 294,302120 Nuclei Using the Relativistic Mean-Field Method

Abstract

We have studied the structure of superheavy nuclei 294,302120 in the framework of a relativistic mean-field formalism, using three different parameter sets (NL1, NL–SH and TM1) in an axially deformed harmonic oscillator basis. The calculated shapes are found to be parameter-dependent, e.g. NL1 parameter set predicts 302120 as a spherical and 294120 a very weakly oblate deformed nucleus whereas NL–SH and TM1 parameter sets predict both the nuclei with strongly prolate/oblate deformed configurations, in their respective ground states. This result, coupled with the calculated single-particle energy spectrum for NL1 parameter set, supports for Z=120 nuclei the spherical magic shell more at N=184 than at N=172. Even for the spherical 302120 nucleus, many new closed shells are predicted and some of the known magic numbers are found absent. Also, the binding energies of the various isotopes of Z=104–111 nuclei are calculated whose comparisons with experimental data favor the NL1 parameter set.