Detection of rare isotopes by the collinear laser photoionization of accelerated atoms

Experimental results are presented which demonstrate that the collinear laser photoionization of accelerated atoms is a sensitive and highly selective technique for the analysis of isotopic composition. This technique guarantees an additional isotopic shift in the absorption spectra of atoms at any atomic transition, and makes it possible to use existing dye lasers to achieve isotopically selective excitation of atoms with high (about 20 eV) ionization potentials which have high metastable levels.