A COMPUTER-CONTROLLED APPARATUS FOR CYCLIC INSTRUMENTAL CPAA

An apparatus for cyclic charged particle activation was designed, buil t and connected to the 7 MV Van de Graaff CN accelerator of the Labora tori Nazionali dell'Istituto Nazionale di Fisica Nucleare di Legnaro ( Italy). It mainly consists of a two-sample transverse moving system co ntrolled by a Cycle Control Module (CCM). This module is based on a Pr ogrammable Logic Device (PLD) for the definition of the requested flow -maps and functions. The CCM operates the cc motor for sample movement s by means of a power width modulation technique. It also controls the beam switch and the setting mode of the acquisition system which is c onnected to two HPGe detectors. As a feasibility test, the best experi mental conditions for aluminium determination in complex. Al-doped bio logical samples were found to be an irradiation time of 3.5 minutes an d a measuring time of 6 minutes. The signal to background ratio is rep orted as a function of the number of cycles.