Theoretical determination of energies, wavelengths, and transition rates for the Y[formula omitted]–Y[formula omitted] spectra of fusion interest

Abstract

We report a set of theoretical data for the energy levels, wavelengths, transition rates of electric/magnetic-dipole (E1/M1) and electric/magnetic-quadrupole (E2/M2) transitions for the L-shell charge states of Y30+, Y31+, Y32+, Y33+, Y34+, and Y36+ and the similar spectroscopic data of the 166 fine-structure levels arising from the 2s2, 2s2p, 2p2, 2snl (n=3,4,5; l=0,1,2,3,4), and 2pnl (n=3,4,5; l=0,1,2,3,4) configurations of Y35+, obtained using the second-order relativistic many-body perturbation theory (MBPT). The overall quality of the calculations is assessed by comparisons with the other available theoretical values and the measured spectra in the Electron Beam Ion Trap (EBIT) of the National Institute of Standards and Technology (NIST). For these yttrium ions, only a few levels have been experimentally established. The accuracy of our calculations is however high enough to facilitate identifications of observed lines. The present new data, fill in a gap in the available data of the extreme ultraviolet (EUV) transitions for these ions particularly important for fusion research where their spectra can provide diagnostic information on hot plasmas, in particular in fusion devices.