Theoretical investigation of energy levels and transition data for P II

Aims. The main goal of this paper is to present accurate and extensive transition data for the P II ion. These data are useful in various astrophysical applications. Methods. The multiconfiguration Dirac-Hartree-Fock (MCDHF) and relativistic configuration interaction (RCI) methods, which are implemented in the general-purpose relativistic atomic structure package GRASP2K, were used in the present work. In the RCI calculations the transverse-photon (Breit) interaction, the vacuum polarization, and the self-energy corrections were included. Results. Energy spectra are presented for 48 even states of the 3S(2)3p(2) ,3s(2)3p{4p, 4f, 5p, 5f, 6p}, 3s3 p(2)3d configurations, and for 58 odd states of the 3s3p(3) , 3s(2)3p{3d, 4s, 4d, 5s, 5d, 6s} configurations in the P II ion. Electric dipole (E1) transition data are computed between these states along with the corresponding lifetimes. The average uncertainty of the computed transition energies is between five and ten times smaller than the uncertainties from previous calculations. The computed lifetimes for the 3s(2)3p4s(3)P degrees states are within the error bars of the most current experimental values