Positron-induced proton desorption from Ni surfaces

Positron-induced ion-desorption spectroscopy has been constructed and used for measurements of positron-induced hydrogen ion desorption from Ni surfaces. The cross-section for proton desorption at a positron incident energy of 1.9 keV was larger than that at a positron incident energy of 2.9 keV. This value is larger than that for electron-stimulated desorption with similar incident energies, suggesting that ion desorption is caused by the thermalized positrons in the bulk.