Storage-ring measurements of hyperfine induced transition rates in berylliumlike ions

Abstract

Articles you may be interested inMassively parallel implementations of coupled-cluster methods for electron spin resonance spectra. I. Isotropic hyperfine coupling tensors in large radicals

Electron–ion merged-beam experiments at heavy-ion storage rings

“…Figure 5 summarizes the state-of-the-art for electron-ion recombination of W 20+ ([Kr] 4d 10 4 f 8 ). As in the case of isoelectronic Au 25+ , the measured merged-beam rate coefficient (Schippers et al 2011) at low electron-ion collision energies is more than two orders of magnitude larger than the theoretical rate coefficient for RR. Up to energies 2011) from the TSR storage ring.…”

“…Accurate atomic data are required for the modeling of radiation losses from the fusion plasma due to impurity ions, and recombination rate coefficients for tungsten ions are of particular concern (Pütterich et al 2008). For W 20+ (Schippers et al 2011) and W 18+ (Spruck et al 2014) it was found that in the temperature ranges where these ions form in a collisionally ionized plasma the experimentally derived plasma recombination rate coefficients exceed the ones from the ADAS atomic data base (ADAS 2014) by up to an order of magnitude. below ∼ 10 eV the result of the standard DR calculation of Badnell et al (2012, full curve) is a factor of three lower than the experimental curve.…”

“…As in the case of isoelectronic Au 25+ , the measured merged-beam rate coefficient ) at low electron-ion collision energies is more than two orders of magnitude larger than the theoretical rate coefficient for RR. Up to energies Schippers et al (2011) from the TSR storage ring. In the displayed energy range it is almost three orders of magnitude larger than the theoretical rate coefficient for radiative recombination (RR, red dashed line, from Schippers et al 2011).…”

“…Up to energies Schippers et al (2011) from the TSR storage ring. In the displayed energy range it is almost three orders of magnitude larger than the theoretical rate coefficient for radiative recombination (RR, red dashed line, from Schippers et al 2011). The blue full line and the blue dash-dotted line are the results of standard DR theory and of undamped statistical theory, respectively, from Badnell et al (2012).…”

“…Figure5: Merged-beams rate coefficients for recombination of W 20+ ([Kr] 4d 10 4 f 8 ) ions with free electrons. Symbols denote experimental results ofSchippers et al (2011) from the TSR storage ring. In the displayed energy range it is almost three orders of magnitude larger than the theoretical rate coefficient for radiative recombination (RR, red dashed line, fromSchippers et al 2011).…”