Photoionization of potassium atoms from the ground and excited states

The B-spline Breit-Pauli R-matrix method is used to investigate photoionization of atomic potassium from the ground 3p64s 2S1/2 and excited 3p64p 2Po1/2,3/2 states. The nonorthogonal orbitals have been used for an accurate representation of the initial K bound states, the final K+ ion plus photoelectron states and K+ thresholds. The 43 K+ fine-structure levels of the 3p6, 3p54s, 3p53d, 3p54p, 3p55s and 3p54d configurations have been included in the photoionization calculations. The relativistic effects have been incorporated in the Breit-Pauli Hamiltonian.