Extreme-ultraviolet wavelength and lifetime measurements in highly ionized krypton

We have studied the spectrum of highly ionized krypton in the extreme-ultraviolet wavelength region (50–300 Å), using beam-foil excitation of fast krypton ions at the Argonne ATLAS accelerator facility. We report measurements of transition wavelengths and excited-state lifetimes for n = 2 states in the lithiumlike, berylliumlike, and boronlike ions, Kr31+,32+,33+. Excited state lifetimes ranging from 10 ps to 3 ns were measured by acquiring time-of-flight-delayed spectra with a position-sensitive multichannel detector.PACS Nos.: 32.70.Cs, 32.30.Jc, 34.50.Fa