Optogalvanic isotope enrichment of Cu ions in Cu-Ne positive column discharges.

The isotopic enrichment of copper ions in a positive column Cu-Ne discharge using optogalvanic excitation is analyzed with a rate equation model. With excitation at 510.6 nm, the fraction of the ions belonging to the 63-amu isotope of copper is enriched relative to the neutral abundance. Enrichment as large as 10% is calculated when the initial abundance of the neutral isotope is small (<0.1) and the discharge current density is large (>75 mA/cm ). The degree of enrichment is examined as a function of the initial abundance, discharge current, the rate of charge exchange, and the diameter of the discharge tube.