Spectroscopy of 2s[subscript 1/2]-2p[subscript 3/2] transitions in W[superscript 65+] through W[superscript 71+]

Abstract

A high-resolution flat-crystal spectrometer was used on the SuperEBIT electron beam ion trap to measure the energies of the 2s[subscript 1/2]-2p[subscript 3/2] transitions in lithiumlike through fluorinelike tungsten. These transitions are strongly affected by energy shifts due to quantum electrodynamics (QED). SuperEBIT was run at an electron energy of 103.2±0.5 keV and an electron beam current of 150 mA to generate the respective charge states; hydrogenlike aluminum and neonlike krypton were used as calibration elements. The spectra were analyzed with and the results compared to calculations based on the flexible atomic code. Good agreement was found. The measurements yielded line positions with a precision of 1–2 eV, which test QED calculations to 5%–10%.