Atomic data of Cu i for the investigation of element abundance

Abstract

A complete set of atomic data of Cu I, including the energy levels, oscillator strengths, and photoionization cross sections, is theoretically studied to investigate element abundance including nonlocal thermodynamic equilibrium (NLTE) effects. The calculations are carried out by using the R-matrix method in the LS-coupling scheme. Twenty terms of Cu II are utilized as target states, and extensive configuration interactions are included to properly delineate the quantum states of Cu II and Cu I. One hundred thirteen bound states and 1699 oscillator strengths for E1 transitions between these states are obtained. Photoionization cross sections for all bound states are calculated in a photon energy range covering 1.28 Ry from the threshold of the respective state. Resonances shown in the photoionization cross sections are identified, and some strong resonances are expected to play an important role in NLTE modeling. The atomic data in this work represent the first complete data set for copper abundance studies. Our results are compared with the experimental and other theoretical data wherever available. © 2014. The American Astronomical Society. All rights reserved..