Theoretical studies on structural properties and decay modes of ^284-375 119 isotopes

Within the axially deformed relativistic mean field with NL3^* parametrisation, the different bulk properties like binding energy, quadrupole deformation parameter, separation energies, density profile and shape co-existence for Z = 119 isotopic chain within the mass range 284 ≤ A ≤ 375 are computed. Further, a competition between possible decay modes such as α-decay, β -decay and spontaneous fission (SF) of the isotopic chain of Z = 119 superheavy nuclei under study is systematically analysed within self-consistent relativistic mean field model and a close agreement is noticed among the calculations performed using various semi-empirical formulae and also with the estimations made by finite range droplet model (FRDM) wherever available. Our analysis confirmed that α–decay is restricted within the mass range 284 ≤ A ≤ 375 and thus being the dominant decay channel in this mass range and there is no possibility of β –decay for the considered isotopic chain. In addition, we forecasted the α–decay chain of fission survival nuclides, i.e. ^284-296119 and found as one α chain from ^284 119 and ^296 119 , 2 α chains from ^285119 and ^295 119 consistently, 3α chains from ^286 119 and ^294 119 consistently, 4 α chains from ^287 119 consistently, six consistent α chains from ^288-293 119 . A comparative study of SF and α-decay half-live computed using the formula of Santhosh et al and Coulomb proximity potential model (CPPM), respectively, for the fission surviving isotopic chain reveals that isotopes ^288-293 119 exhibit 6α chains followed by SF, isotopes ^295,296 119 exhibit 4α chains followed by SF, and the rest of the nuclei show continuous α chains. This study has also established that the alpha half-life values computed using Q_α (RMF) agree with half-life values computed using experimental Q_α values within 1 order difference. Thus, such studies can be of great significance to the experimentalists in very near future for synthesizing the isotopes of Z = 119 superheavy nuclei.