THE IRON PROJECT \& Opacity Project: Photoionization of iron ions for Opacities and collisional excitations of P III

POSTER

Abstract

Fe~XVIII is the 2nd most abundant iron ion and probably the most contributing ion to opacity near the boundary between radiative and convection zones in the sun. The current poor agreement of the higher opacity from the 3D astrophysical model as well as and measurement at Z-pinch with the predicted opacity is considered to be due to lower estimation in photoionization cross sections ($\sigma_{PI}$) of Fe XVII - XIX in the existing data. In order to obtain high accuracy $\sigma_{PI}$ with high energy resonant features, a large-scale computation has been started for $\sigma_{PI}$ of Fe!XVIII in the relativistic Breit-Pauli R-matrix (BPRM) method and using a large wavefunction expansion. Work is in progress to resolve all the computational challenges and preliminary results will be presented. Collision strengths for P III is also under investigation using BPRM method and a wavefunction expansion of 18 levels as the lines of this basic element of life have been detected recently. Features in collision strengths and selected line ratios for low lying levels for diagnostics of plasmas obtained from preliminary results will be presented.

Authors

  • W. Eissner

    Stuttgart University

  • L. Zhao

    Ohio State Univ - Columbus

  • Rahla Naghma

    Ohio State Univ - Columbus

  • Sultana Nahar

    Ohio State Univ - Columbus, Department of Astronomy, The Ohio State University, Te Ohio State University

  • Anil Pradhan

    Ohio State Univ - Columbus, Biophysics Graduate Program, Department of Astronomy, Chemical Physics Graduate Program, The Ohio State University, Te Ohio State University