Electron Impact Excitation Collision Strengths and Rates for P ii

Abstract

The Breit-Pauli R-matrix method has been used to calculate electron collisional excitation strengths for transitions between the 41 lowest fine-structure levels of the 3s23p2, 3s3p3, 3s23p3d, 3s23p4s, and 3s23p4p configurations in P II. Accurate representation of target levels have been obtained on the basis of configuration-interaction wave functions. The relativistic effects in the scattering equations are included through mass correction, Darwin, and spin-orbit operators of the Breit-Pauli Hamiltonian. The collision strengths in the threshold energy regions are dominated by complicated resonance structures. The effective collision strengths are determined by integrating collision strengths and assuming a Maxwellian distribution of electron energies. The effective collision strengths are listed over a wide temperature range (103-106 K) applicable to astrophysical plasmas.