Abstract

The spectrum of the copperlike ion Sr x was observed with a low-inductance spark in the region 70–630 Å on the 10.7-m grazing-incidence spectrograph at the National Bureau of Standards. From the identification of 30 lines, a system of 23 energy levels of the type 3d¹⁰nl was determined. The level system includes the configurations ns (n = 4–7), np (n = 4–6), nd (n = 4–6), nf (n = 4–6), and ng (n = 5). The 4f ²F term is inverted. Also identified were 12 transitions of the type 3d¹⁰4s–3d⁹4s4p and 3d¹⁰4p–3d⁹4p², permitting the determination of several 3d⁹4s4p and 3d⁹4p² levels. The observed 3d¹⁰nl energy levels and parameters are compared with Hartree–Fock calculations. The ionization energy is determined from the 3d¹⁰ns and nf series to be 1 430 000 ± 500 cm⁻¹ (177.30 ± 0.06 eV). Data for 3d–4p transitions in Sr ix and Sr xi and 3p–3d transitions in Sr xii are also presented.

© 1981 Optical Society of America

Spectrum and energy levels of eleven-times ionized zirconium (Zr xii)

Joseph Reader and Nicolo Acquista
J. Opt. Soc. Am. 69(12) 1659-1662 (1979)

Spectrum and energy levels of twelve-times ionized niobium (Nb xiii)

Joseph Reader and Nicolo Acquista
J. Opt. Soc. Am. 70(3) 317-321 (1980)

Spectrum and energy levels of thirteen-times ionized molybdenum (Mo xiv)

Joseph Reader, Gabriel Luther, and Nicolo Acquista
J. Opt. Soc. Am. 69(1) 144-149 (1979)

Spectrum and energy levels of ten-times ionized yttrium (Y xi)

Joseph Reader and Nicolo Acquista
J. Opt. Soc. Am. 69(9) 1285-1288 (1979)

Spectrum and energy levels of eight-times ionized rubidium (Rb ix)

Samuel Goldsmith, Joseph Reader, and Nicolo Acquista
J. Opt. Soc. Am. B 1(4) 631-634 (1984)