Isotope shift studies in neodymium spectra. I

The isotope shift Δsigma (142Nd-144Nd) has been recorded in 311 lines of the neodymium spectrum in the region 3900-4760 A on a recording Fabry-Perot spectrometer using enriched isotopes. Large isotope shifts have been observed mostly in transitions involving 4f35d6s2 configuration of Nd I as the lower level. Transitions involving thirteen levels assigned to the f4p configuration of Nd II have been studied and the extent of configuration mixing in these levels has been discussed. A few lines were found very close to some of the listed lines. The 'source-exchange' technique was employed for measuring the isotope shift in these and other close lines. (Auth.)