Time resolved EUV spectroscopy on foil-excited 5.9 MeV/u Xe and 13.2 MeV/u Au ions

Abstract

N= 3, An=O transitions in Na-like ions have been observed and the resonance level lifetimes have been measured by time-resolved spectroscopy of foil-excited ion beams of Xe (Z = 54) and Au (Z = 79). Other lines in the same wavelength range are identified with n=3, An=O transitions in Ne-, Mg-, and Al-like ions. Wavelengths and transition rates for these new lines are compared to the available theoretical data. A number of experimental problems are discussed.

Relativistic multireference many-body perturbation theory calculations on F-, Ne-, Na-, Mg-, Al-, Si- and P-like xenon ions

“…The experimental set-up of the beam-foil work on Xe and Au at the Darmstadt (Germany) GSI UNILAC accelerator has been described elsewhere [7][8][9]. This experimental arrangement has gone through various development stages; most of the experimental effort was directed at the precision spectroscopy of few-electron ions, in particular the determination of QED contributions to the transition energies of n = 2-2 transitions in Li-and Be-like ions [34][35][36][37][38].…”

“…The Xe experiment [7,8] aimed primarily at spectra from which decay curves of the resonance lines of Na-like Xe ions were to be constructed and then atomic level lifetimes and transition probabilities derived. The wavelengths of the 3s-3p-3d transitions in Na-like ions can be calculated well enough for such purpose.…”

“…However, a constant dispersion was a reasonable approximation for only two of the three spectral slices, but not for the third. At short wavelengths, the dispersion (wavelength interval divided by distance along the Rowland circle circumference) progressively changes, and it should not have been taken as constant in [8]. Taking the spectrometer geometry into better account (now for all spectral sections covered), changes the dispersion notably, so that-with reference to the same line of Na-like Xe in the short-wavelength spectrum-the probable identifications of several other lines change.…”

“…The 1995 beam-foil spectra [8] mostly cover three spectral sections within the wavelength range from 50-150 Å. The spectra have been recorded at various foil displacements (up to 28 positions) from the line of sight of the spectrometer, corresponding to observations in a range of delays after excitation.…”

“…We resort to experimental data for atomic systems well beyond the bulk of well-analysed spectra, and thus with some uncertainty in the earlier line classifications. The data are from a series of beam-foil experiments on Xe and Au [7][8][9] that have, about a decade ago, pushed the envelope of such enterprises. (One of us, ET, was the lead author of those three studies, and some of the laboratory notes and other unpublished materials of the time are available to us for a re-investigation.)…”