CHARGE-EXCHANGE AND STOPPING POWER OF CHANNELED HEAVY-IONS

We investigated the exit charge, scattering angle and energy loss dist ribution of heavy ions (30 MeV carbon) planar channeled in a thin crys tal. We measured, in a list mode, exit charge q(ex), scattering angle theta(ex) with respect to the (110) channeling plane, and energy loss Delta E, for each heavy ion of incident charge q(in) and incident angl e theta(in), and obtained a distribution Y(theta(sc),q(ex),Delta E;the ta(in),q(in)). As a single crystal, we adopted a thin totally depleted Si detector of 4 mu m in thickness, and we measured the energy loss b y the signal of the detector itself. After passing through the sample crystal, the exit charge and angle of the ions were measured with a 2D position sensitive detector coupled with a slit and an electrostatic deflector. Close correlations among the exit charge, energy loss and e xit angle were found.