Energies of the n2S [formula omitted] and n2D [formula omitted], [formula omitted] states of Cs

Abstract

Using the technique of Doppler-free two-photon spectroscopy the energies of the n 2S 1 2 (12 ⩽ n ⩽ 35) and n 2D 3 2 , 5 2 (11 ⩽ n ⩽ 48) states of CsI have been measured with a thermionic detector. The absorption spectrum of molecular iodine was used as a reference giving us a total estimated accuracy of about 2 × 10 -7. Taking also into account the energies of the 7–11 2S 1 2 and 5 and 6 2D 3 2 , 5 2 states measured by other authors and using an extended Ritz-formula we found the ionization limit to be E i = 31406.468 ± 0.006 cm -1.