Plasmon production by the decay of hollow Ne atoms near an Al surface - art. no. 052902

Measurements of low-energy electrons emitted by 4.5-keV Neq+-ion impact on an Al surface are discussed for incident charge states q = 1-6. Spectral st ructures found near 11 eV are attributed to the decay of bulk plasmons. A m ethod is given to determine absolute values for the experimental electron y ield from the plasmon decay. Absolute plasmon yields are studied as a funct ion of the incidence angle of the projectile and the observation angle of t he electron. A cosinelike angular distribution is found for the ejected ele ctrons indicating that the plasmons decay well below the surface. The exper imental data are compared with model calculations providing information abo ut the plasmon production mechanisms.