Wavelengths of the4s1/2−4p3/2resonance lines in Cu-like heavy ions

Abstract

The euv resonance lines 4s{sub 1/2}-4p{sub 3/2} of the Cu- and Zn-like ions of Os, Bi, Th, and U (Z=76-92) have been observed in an electron beam ion trap, and their wavelengths measured using a high-resolution flat-field spectrometer. Our experiments achieve a spectral resolution three to six times better than earlier measurements and remove potential systematic errors from line blends encountered in earlier work. Our results for Cu-like ions are in good agreement only with recent ab initio calculations that include quantum electrodynamical effects. Our experimental results for Zn-like ions have a similarly high accuracy. However, theoretical predictions for Zn-like ions of a quality comparable to those available for Cu-like ions are lacking.