Pairing gaps and Fermi energies at scission for 296Lv alpha-decay

TL;DR

This paper investigates pairing corrections and single particle levels at nuclear scission in alpha decay of superheavy element 296Lv, revealing how pairing gaps and particle occupations evolve during the fission process.

Contribution

It introduces a detailed microscopic analysis of pairing gaps and single particle states at scission using a Woods-Saxon two-center shell model and density-dependent delta interaction formalism.

Findings

Pairing gaps are large at scission but vanish after.

1s1/2 levels of alpha are fully occupied at scission.

Nascent alpha forms a very bound cluster at scission.

Abstract

The pairing corrections, the single particle occupation numbers, are investigated within density-dependent delta interaction formalism for pairing residual interactions. The potential barrier is computed in the framework of the macroscopic-microscopic model. The microscopic part is based on the Woods-Saxon two center shell model. The alpha-decay of a superheavy element is treated, by paying a special attention to the region of the scission configurations. The sequence of nuclear shapes follows the superasymmetric fission path for alpha decay. It was found that the pairing gaps of the states that reach asymptotically the potential well of the alpha particle have large values at scission but become zero after scission. The 1s1/2 single particle levels of the nascent alpha particle are fully occupied while the superior levels are empties in the scission region and remains in the same states during the penetration of the Coulomb barrier. The projection of the numbers of particle on the two fragments are obtained naturally. At scission, the nascent alpha particle forms a very bound cluster.