An investigation of resonances in e+-H scattering embedded in Debye plasma

We carry out calculations for S-wave and P-wave resonances in e(+)-H scattering in weakly coupled Debye plasma in which the interaction between two charged particles is represented by a screened Coulomb potential. We employ the complex-scaling method with Hylleraas-type basis set to take correlation effects into account. In the complex-scaling treatment of the screened Coulomb potential, we first perform a Taylor series expansion for the exponential function that contains the distance r between two particles into a polynomial with various powers r(n). We then make the complex scaling transformation of r -> r e(i theta) in the expansion. The complex resonant eigenvalues are obtained by searching for stabilized points in the complex energy plane with respect to the changes of rotational angle theta and other parameters in the basis set. (C) 2015 AIP Publishing LLC.