α-decay chains of 173288115 and 172287115 in the relativistic mean field theory -: art. no. 061303

In the recent experiments designed to synthesize the element 115 in the (243)AM+Ca-48 reaction at Dubna in Russia, three similar decay chains consisting of five consecutive alpha decays and another different decay chain of four consecutive alpha decays are detected, and the decay properties of these synthesized nuclei are claimed to be consistent with consecutive alpha decays originating from the parent isotopes of the new element 115, (288)115 and (287)115, respectively. Here in the present work, the recently developed deformed relativistic mean field+BCS method with a density-independent delta function interaction in the pairing channel is applied to the analysis of these newly synthesized superheavy nuclei. The calculated alpha-decay energies and half-lives agree well with the experimental values and with those of the macroscopic-microscopic finite-range droplet model with folded-Yukawa single-particle potentials and Yukawa-plus-exponential model with Woods-Saxon single-particle potentials. In the mean field Lagrangian, the TMA parameter set is used. Particular emphasis is laid on the influence to both the ground-state properties and energy surfaces introduced by different treatments of pairing. Two different effective interactions in the particle-particle channel, i.e., the constant pairing and the density-independent delta-function interaction, together with the blocking effect are discussed in detail.