Longevity studies on the J=2 even-parity Rydberg series of CdI

An analysis of Cd I's existing experimental energy levels and lifetimes are given by Multichannel Quantum Defect Theory(for short MQDT).On this condition,the energy spectrum of Cd I even-parity J=2,a model having one ionization limit and two channels is adopted,and its MQDT parameters are obtained by fitting experimental spectrum data.A general calculation method of the lifetime of high excited state is obtained by means of wave function of MQDT.Then the total 18 energy levels and lifetimes of 5snd1/2[5/2]2(6≤n≤23)Rydberg series were derived from the calculation,and 4 new energy levels and 14 new lifetimes of this series' Rydberg state are predicted.In addition,the fitted formula of their lifetimes is given as follows:τ=0.3963ν2.784n.