High-resolution laser spectroscopy of the hyperfine structure of high-lying levels of Nb i

Abstract

High-resolution laser spectroscopy techniques have been applied in the wavelength range between 645 and 675 nm to measure the hyperfine structure (hfs) of high-lying levels of atomic niobium. Using Doppler-limited optogalvanic spectroscopy 20 well-resolved spectra were measured and 10 spectra using Doppler-reduced saturation absorption spectroscopy technique. We have precisely determined the magnetic dipole hfs constants A of 42 levels and electric quadrupole hfs constants B of 15 levels. For the first time 17 A constants and 5 B constants were measured.

Hyperfine structure investigations of atomic niobium with optogalvanic and laser-induced fluorescence spectroscopy in the near-infrared wavelength range

“…We here continue our earlier systematic investigations of the spectrum of Nb I Kröger et al 2004Kröger et al , 2007Kröger et al , 2010Başar et al 2008;Er et al 2011). Our purpose is to supplement hyperfine structure (hfs) data for this element, in particular, to fill gaps for all energy levels of even parity with unknown hyperfine structure (hfs) constants.…”

“…t.w. : this work; (1) Fraenkel et al (1988); (2) Er et al (2011); (3) Bouzed et al (2003); (4) Başar et al (2008); (5) Kröger et al (2010). Notes.…”

“…For the low-lying energy levels hfs constants have been determined with very high accuracy using atomic-beam magnetic-resonance method by . Other high-resolution measurements have been made by Fraenkel et al (1988) using laser and radio-frequency spectroscopy, and by some of us (Başar et al 2008), using Doppler-reduced saturation absorption spectroscopy. Doppler-limited measurements of hfs constants have been made using Fourier transform spectroscopy (Kröger et al 2010;Er et al 2011) and Doppler-limited laser spectroscopic methods (Singh & Rao 1989;Singh et al 1992;Bouzed et al 2003;Kröger 2007).…”

Hyperfine structure measurements of neutral niobium with Fourier transform spectroscopy

“…The fine and hyperfine structure of atomic niobium has been the subject of several experimental and theoretical investigations (Başar et al 2008;Kröger 2007;Kröger et al 2007Kröger et al , 2004Bouzed et al 2003;Singh et al 1992;Singh & Rao 1989;Fraenkel et al 1988). All recent experimental work has been performed using laser spectroscopic methods, which are restricted in the wavelength range accessible to the cw-lasers currently in use.…”

“…( * ) FWHM and ratio between Gaussian and Lorentzian FWHM fixed during the fit; ( †) error in sign in Başar et al (2008); ( ‡) ΔA fit is set equal to the uncertainty of the A l -constant of the lower level.…”