Half-life of excited state

Values calculated by means of these formulas for the half-life of excited states are listed in Table 5.3. Because not all properties of nuclei are considered in the model, the table gives only approximate values. 

Bi3 A32 - strong absorption, long half-life of excited state... 

The half-life of excited states (isomers) depends on the change of nuclear spin (AI) and parity in the transition as well as on the transition energy (Er). The greater is AI, the longer is Li/2, but an increase in Lr causes a decrease in the half-life. 

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