Any technique using high energy particles directed toward a sample, in which the bombarding particles are detected and recorded as function of energy and/or angle. The technique is mostly used for determining depth distributions of elements based on the energy of the backscattered particle. In general, He⁺ or H⁺ particles are used at energies in the order of 100 keV to some MeV. Also referred to as backscattering spectrometry (BSS).