Laser-rf double-resonance spectroscopy in the samarium i spectrum: Hyperfine structures and isotope shifts

Abstract

High-resolution laser-rf double-resonance spectroscopy has been performed in the $4{f}^{6}6{s}^{2}^{7}F_{6}$ (4020.66 ${\mathrm{cm}}^{\ensuremath{-}1}$), $4{f}^{6}5d6s^{9}H_{2}$ (11044.90 ${\mathrm{cm}}^{\ensuremath{-}1}$), $4{f}^{6}5d6s^{9}H_{3}$ (11406.50 ${\mathrm{cm}}^{\ensuremath{-}1}$), and $4{f}^{6}5d6s^{7}H_{3}$ (13542.80 ${\mathrm{cm}}^{\ensuremath{-}1}$) metastable levels of Samarium i. Hyperfine parameters have been deduced with an absolute accuracy of \ensuremath{\sim} 2 kHz. By means of laser-induced fluorescence, hyperfine constants have been determined in excited levels up to \ensuremath{\sim} 30560 ${\mathrm{cm}}^{\ensuremath{-}1}$, and isotope shifts measured for 11 lines.