Fe IX Calculations for the Solar Dynamics Observatory

TL;DR

This paper presents new atomic data calculations for Fe IX, crucial for interpreting solar observations, especially affecting the analysis of SDO AIA 94Å filter data.

Contribution

It provides updated energy levels, transition rates, and collisional excitation data for Fe IX, extending previous calculations to higher energy levels with improved accuracy.

Findings

Predicted significant emission in 5f-3d transitions.

Enhanced atomic data for better solar observation analysis.

Implications for SDO AIA 94Å filter data interpretation.

Abstract

New calculations of the energy levels, radiative transition rates and collisional excitation rates of \ion{Fe}{ix} have been carried out using the Flexible Atomic Code, paying close attention to experimentally identified levels and extending existing calculations to higher energy levels. For lower levels, R-matrix collisional excitation rates from earlier work have been used. Significant emission is predicted by these calculations in the 5f-3d transitions, which will impact analysis of SDO AIA observations using the 94\AA\ filter.