EUV spectroscopy of highly charged iron ions with a low energy compact EBIT

Abstract

We measured extreme ultraviolet (EUV) spectra of highly charged iron ions (Fe IX -Fe XV) in the range of wavelength 130-300 Å by a new compact electron beam ion trap (EBIT) which was developed for low electron energy operation. The electron energy of this compact EBIT is controllable from 100 eV to few keV, therefore it is appropriate for spectroscopic investigation of the moderately charged ions. A slitless flat-field EUV spectrometer developed exclusively for this compact EBIT is mounted with it and high sensitivity and high resolution spectroscopic analysis of highly charged iron ions become possible. The electron energy dependence of highly charged iron ion spectra were measured in the range of electron energy of 200-1350 eV. We could get the spectral information of wide range of charge state from Fe IX to Fe XV, and moreover, various charge state ions could be selectively produced with a narrow charge state distribution by adjusting the electron beam energy.