ELECTRONIC STOPPING POWER MEASUREMENTS USING SECONDARY-ION BEAMS

Stopping powers for O and Ti ions were measured in a mylar foil 2 mum thick. The choice of the foil was made because of its wide application in elastic recoil detection analysis experiments and thin windows for gaseous detectors. As a new approach, recoil ions produced in heavy ion scattering were utilized for (dE/dx) measurements. The energy loss of the recoil ions was measured by keeping two surface barrier detectors, with and without the mylar foil, at the same recoil angle, with their gains matched with pulsers before the experiment. Different energies of the secondary beam could be selected by changing the detection angle. Also, various species of secondary ions could be obtained by merely changing the target. We demonstrate here our new technique and some of the results obtained.