Mass Spectrometric Investigation of Surface Ionization. VI. Desorption of Th+, Np+, and Pu+ from Tungsten Surfaces

Abstract

The mean residence times of Th+, Np+, and Pu+ on polycrystalline tungsten surfaces have been determined as functions of temperature using the modulated beam technique. The desorption parameters, determined from the relationship 1 / τ = ω0exp(− Ei / kT), are Ionω0(sec−1)Ei(eV)Th+(1.7 ± 1.5) × 10147.83 ± 0.25Np+(6.8 ± 3.8) × 10136.32 ± 0.12Pu+(1.6 ± 0.9) × 10124.99 ± 0.15.