Doubly excited inter-shell P-wave resonances of helium in weakly coupled plasmas

We have investigated the doubly excited 1,3Po resonance states of helium embedded in weakly coupled plasmas. A screened Coulomb potential obtained from the Debye model is used to represent the interaction between the charge particles. A correlated wavefunction consisting of a generalized exponential expansion has been used to represent the correlation effect. A total of 18 resonances (9 each for 1Po and 3Po states) below the n = 2 He+ thresholds has been estimated by calculating the density of states using a stabilization method. For each spin state, this includes four members in the 2snp+(2 ⩽ n ⩽ 5) series, three members in the 2snp−(3 ⩽ n ⩽ 5) series, and two members from 2pnd(n = 3, 4) series. The resonance energies and widths for various Debye parameters ranging from infinity to a small value for these 1,3Po resonance states are reported. In addition, the wavelengths for the photo-absorption of a helium atom from its ground state to such 1Po resonance states for different Debye lengths are also reported.