A new empirical formula for α-decay half-life and decay chains of Z=120 isotopes
arXiv:2107.12976 · doi:10.1088/1402-4896/ac1a4d
Abstract
Experimental -decay half-life, spin, and parity of 398 nuclei in the range 50Z118 are utilized to propose a new formula (QF) with only 4 coefficients as well as to modify the Tagepera-Nurmia formula with just 3 coefficients (MTNF) by employing nonlinear regressions. These formulas, based on reduced mass () and angular momentum taken away by the -particle, are ascertained very effective for both favoured and unfavoured -decay in addition to their excellent match with all (Z, N) combinations of experimental -decay half-lives. After comparing with similar other empirical formulas of -decay half-life, QF and MTNF formulas are purported with accuracy, minimum uncertainty and deviation, dependency on least number of fitted coefficients together with less sensitivity to the uncertainties of -values. The QF formula is applied to predict -decay half-lives for 724 favoured and 635 unfavoured transitions having experimentally known -values. Moreover, these available -values are also employed to test various theoretical approaches viz. RMF, FRDM, WS4, RCHB, etc. along with machine learning method XGBoost for determining theoretical -values, incisively. Thereafter, using -values from the most precise theoretical treatment mentioned above along with the proposed formulas, probable -decay chains for Z120 isotopes are identified.
Accepted in Physica Scripta-IOPscience