Empirical Formulae to Calculate the Half-life of E1 Gamma Transitions for Selected Isotopes

In the present work, the mass number (A), gamma decay energy (E), and half-life(T1/2) of E1 gamma-transitions data taken from the nuclear data centers for theisotopes (22Ti48, 21Sc46, 25Mn56, 26Fe59, 36kr87, 33As81) have been used to findempirical formulae for calculating the half-life (T1/2) of such transitions. Two newestablished empirical formulae combines the gamma transition energies with theasymmetry factor (N-Z)/A in the first formula and the binding energy in the secondformulae. A good agreement has been recorded for the experimental half-life takenfrom ENSDF and ENDF with those evaluated using the established formulae. Inboth cases the calculated half-life was in good agreement with the declaredexperimental data.