Alpha decay chains study for the recently observed superheavy element Z=117 within the Isospin Cluster Model

TL;DR

This paper uses the Isospin Cluster Model to analyze alpha decay chains of superheavy element Z=117, providing theoretical predictions that align well with experimental data and suggesting a magic neutron number at N=172.

Contribution

The study introduces an improved Isospin Cluster Model with isospin-dependent radii to accurately predict alpha decay properties of superheavy nuclei, comparing results with experimental and other theoretical models.

Findings

Calculated alpha decay half-lives agree with experimental data.

Supports the existence of a magic neutron number at N=172.

Provides detailed Q-values and decay properties for Z=117 decay chains.

Abstract

The recently observed $\alpha$-decay chains $^{293-294}117$ were produced by the fusion reactions with target $^{249}Bk$ and projectile $^{48}Ca$ at Dubna in Russia. The reported cross-sections for the mentioned reaction are $\sigma=0.5(+1.1,-0.4)$pb and $\sigma$=1.3(+1.5,-0.6)$pb$ at $E^{*}=35MeV$ and $E^{*}=39MeV$, respectively. The Q-values of $\alpha$-decay and the half-lives $Log_{10}T^{\alpha}_{1/2}$(s) are calculated for the $\alpha$-decay chains of $^{293-294}117$ nuclei, within the framework of Isospin Cluster Model (ICM). In the ICM model the proximity energy is improved by using the isospin dependent radius of parent, daughter and alpha particle. The binding energy $B(A_{i}, Z_{i})$ (i=1,2) of any nucleus of mass number A and atomic number Z was obtained from a phenomenological and more genaralized BW formula given by \cite{samanta02}. The calculated results in ICM are compared with the experimental results and other theoretical Macro-Microscopic(M-M), RMF(with NL3 and SFU Gold forces parameter) model calculations. The estimated values of $\alpha$-decay half-lives are in good agreement with the recent data. The ICM calculation is in favor of the persence of magic number at N=172.