Estimating the Level of Uncertainty in Electron-Impact Excitation and Photoionisation Rates of Low-Ionised Stages of Ni Ions

Research output: Contribution to journalArticle

102 Downloads (Pure)


Ni IV lines can be used as diagnostics for temperature and density for various astrophysical objects. In addition, ionization of Ni2+ is one of the causes of the opacity in the interstellar medium. We calculate the photoionization of Ni2+ and the electron-impact excitation of Ni3+. We use a fully-relativistic Dirac Atomic R-Matrix Code (DARC) method. We include a large set of configurations in the expansion of the wave functions of the target, up to the n = 6 atomic shell. We show preliminary results for the photoionization cross-sections of Ni2+ and the electron-impact excitation collision strengths of Ni3+. The expected final results can be implemented in the available software packages for astrophysical plasma simulation, such as CLOUDY. We also show a preliminary estimation of the error of the data by the comparison of different sets of calculations.
Original languageEnglish
Article number74
Number of pages7
Issue number3
Publication statusPublished - 18 Jul 2018
EventEuropean Week of Astronomy and Space Science (EWASS) - Arena & Convention Centre (ACC), Liverpool, United Kingdom
Duration: 03 Apr 201806 Apr 2018



  • Opacities
  • Photoionization

Cite this