Additions to the Spectrum of Fe IX in the 110-200 {\AA} Region

TL;DR

This study extends and revises the known spectral lines of Fe IX in the 110-200 Å range, confirming many solar spectrum lines and identifying new ones using advanced spectroscopic techniques.

Contribution

The paper significantly expands and refines the spectral line data for Fe IX, including new identifications and confirmations in the solar spectrum.

Findings

Extended the known lines in the 3p^53d - 3p^54f and 3p^53d - 3p^43d^2 transition arrays

Confirmed most Fe IX line identifications in the solar spectrum

Suggested several new line identifications

Abstract

The spectrum of eight-times ionized iron, Fe IX, was studied in the 110-200 {\AA} region. A low inductance vacuum spark and a 3-m grazing incidence spectrograph were used for the excitation and recording of the spectrum. Previous analyses of Fe IX have been greatly extended and partly revised. The numbers of known lines in the 3p^53d - 3p^54f and 3p^53d - 3p^43d^2 transition arrays are extended to 25 and 81, respectively. Most of the identifications of the Fe IX lines from the 3p^53d - 3p^43d^2 transition array in the solar spectrum have been confirmed and several new identifications are suggested.