Milestones in EBIT spectroscopy and why it almost did not work

Abstract

The electron beam ion trap (EBIT) spectroscopy that now seems routine would not be possible without considerable good luck in several areas of EBIT technology. Among these are X-ray background, ion cooling, neutral gas density, and electron current density and energy control. A favorable outcome in these areas has enabled clean X-ray spectra, sufficient intensity for high-resolution spectroscopy, production of very high-charge states, and a remarkable variety of spectroscopic measurements. During construction of the first EBIT 20 years ago, it was not clear that any of this was possible.PACS Nos.: 34.80.Kw, 32.30.Rj