ENERGY-LOSS IN LARGE-ANGLE SCATTERING OF SLOW, HIGHLY-CHARGED AR IONSFROM A AU SURFACE

Energy loss of slow (v approximate to 0.06 a.u.), highly charged Ar9ions scattered from a Au(111) single-crystal surface has been investig ated for different incident angles (psi=5 degrees and 37.5 degrees) an d a fixed scattering angle of 75 degrees. The energy position of the e lastic peak agrees well with the value expected for the binary elastic scattering. At small incidence angle (5 degrees) an additional inelas tic energy loss was identified in spite of the large scattering angle. This additional energy loss is found to compare well with a combinati on of a modified Firsov model with processes of electron capture, reca pture, Auger transitions, and image charge acceleration during the ion -surface interactions. [S1050-2947(98)09609-7].