Laser optogalvanic spectroscopy of holmium

Abstract

The optogalvanic spectrum of the neutral holmium atom (Ho i) is investigated with both broadband and single-frequency cw dye lasers and a hollow-cathode lamp. Many new Ho i transitions are observed, and their possible classifications are reported. The hyperfine structure of 165Ho (I = 7/2) is recorded in a number of spectral lines, and the data are analyzed to evaluate the magnetic dipole and electric quadrupole interaction constants (A and B factors, respectively) for energy levels of Ho i. The A and B constants for nine excited states, five of which belong to the 4f116s7p high-lying even configuration of Ho i, are reported for the first time to our knowledge.