Kar, S, Ho YK.
2006.
Doubly excited inter-shell P-wave resonances of helium in weakly coupled plasmas. Journal of Physics B: Atomic, Molecular and Optical Physics. 39:2445-2453., Number 11
AbstractWe have investigated the doubly excited 1,3 P o 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 1 P o and 3 P o 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 2s n p + (2 ≤ n ≤ 5) series, three members in the 2s n p − (3 ≤ n ≤ 5) series, and two members from 2p n d( n = 3, 4) series. The resonance energies and widths for various Debye parameters ranging from infinity to a small value for these 1,3 P o resonance states are reported. In addition, the wavelengths for the photo-absorption of a helium atom from its ground state to such 1 P o resonance states for different Debye lengths are also reported.
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