Absorption spectrum of Pb i between 1350 and 2041 Å

Abstract

The high resolution absorption spectrum of Pb i is reported between 1350 and 2041 Å. Transitions are observed from the 6p ² (1/2,1/2)₀, (3/2,1/2)₁, and (3/2,1/2)₂ levels to levels with J ≤ 2 associated with 6pns and 6pnd configurations. Energy levels have been determined with n* values as high as 74. More than 500 spectral features and 370 odd parity energy levels are reported, a major part of which are new. These observations include five electric quadrupole transitions and 31 nuclear-spin-induced transitions from the 207Pb isotope. Ionization limits of 59819.57 ± 0.10 cm−1 and 73900.64 ± 0.10 cm−1 have been determined for levels converging on the $6p²P_{1/2}^{°}$ and $6p²P_{3/2}^{°}$ levels of Pb ii, respectively. An analysis of these data in terms of Lu-Fano graphical methods and multichannel quantum defect parametrization also is presented.