Consider an experiment involving 2.0 MeV ions backscattered to 180 from a 200 nm SiO2 target. (a) Sketch the backscattering spectrum indicating the energies of the features in the spectrum. (b) Assuming that the stopping power is energy independent, show that the ratio of the energy widths of scattering from oxygen and Si can be written as

where K denotes the kinematic factor. (c) Recognizing that energy loss is not energy independent, derive a precise

(KSi+1)/(K0+1) (KSi+1)/(K0+1)