Proposed New Method for Separating Isotopes

Abstract

RECENTLY¹ a double mercury discharge vessel was used (Fig. 1), in which a large current running in the outer vessel irradiated the small current discharge in the inner vessel with 2537 Å resonance radiation. This irradiation caused the running voltage and electron temperature in the inner discharge to be reduced appreciably over the non-irradiated mode of operation. The explanation offered was that the neutral Hg atoms in the inner vessel absorbed the resonance radiation and entered the 6³P₁ state (see Fig. 2), and from this level the atom was ionized by electron impact. In addition the 6³P₀ and 6³P₂ metastable levels are populated from the 6³P₁ level by electron collisions and by cumulative absorption and radiative decay of higher levels. Because the radiation field is doing approximately half the ionization work, the electron temperature drops correspondingly.