Photoionization of tungsten ions: experiment and theory for W${}^{4+}$

Abstract

Experimental and theoretical results are reported for single-photon single ionization of the tungsten ion W${}^{4+}$. Absolute cross sections have been measured employing the photon-ion merged-beams setup at the Advanced Light Source in Berkeley. Detailed photon-energy scans were performed at 200~meV bandwidth in the 40 -- 105~eV range. Theoretical results have been obtained from a Dirac-Coulomb R-matrix approach employing basis sets of 730 levels for the photoionization of W${}^{4+}$. Calculations were carried out for the $4f^{14}5s^{2}5p^{6}5d^2{}^3{\mathrm{F}}_J$, $J$=2, ground level and the associated fine-structure levels with $J$=3 and 4 for the W${}^{4+}$ ions. In addition, cross sections have been calculated for the metastable levels $4f^{14}5s^{2}5p^{6}5d^2{}^3{\mathrm{P}}_{0,1,2},{}^1{\mathrm{D}}_2,{}^1{\mathrm{G}}_4,{}^1{\mathrm{S}}_0$. Very satisfying agreement of theory and experiment is found for the photoionization cross section of W${}^{4+}$ which is remarkable given the complexity of the electronic structure of tungsten ions in low charge states.

arXiv comment15 pages, 3 figures, to appear in the Journal of Physics B: Atomic, Molecular and Optical Physics

References in corpus (12)

• Dielectronic recombination of xenonlike tungsten ions
• Electronic temperatures, densities and plasma X-ray emission of a 14.5 GHz Electron-Cyclotron Resonance Ion Source
• Photoionization of ions with synchrotron radiation: From ions in space to atoms in cages
• Recombination of W18+ ions with electrons: Absolute rate coefficients from a storage-ring experiment and from theoretical calculations
• Valence-shell single photoionization of Kr${}^{+}$ ions: Experiment and Theory
• Coherent and stochastic contributions of compound resonances in atomic processes: Electron recombination, photoionization and scattering
• Valence and L-shell photoionization of Cl-like Argon using R-matrix techniques
• Photoionization of the $3s^{2}3p^4{}^{3}P$ and the $3s^{2}3p^4{}^{1}D,{}^{1}S$ states of sulfur: experiment and theory
• Photoionization of the valence shells of the neutral tungsten atom
• Photoionization of Co${}^{+}$ and electron-impact excitation of Co${}^{2+}$ using the Dirac R-matrix method
• Level-resolved quantum statistical theory of electron capture into many-electron compound resonances in highly charged ions
• Photoionisation of Cl${}^{+}$ from the $3s^{2}3p^4{}^3{P}_{2,1,0}$ and the$3s^{2}3p^4{}^1{D}_2{,}^1{S}_0$ states in the energy range 19 - 28 eV

Cited by in corpus (1)

• Photoionization of tungsten ions: experiment and theory for W${}^{5+}$