Particle detection for future g factor measurements of Coulomb excited radioactive beams

Recent experiments have shown that the technique of Coulomb excitation of b eam ions in inverse kinematics, where the target nuclei are lighter than th e beam, combined with transient magnetic fields, provides a powerful method to measure magnetic moments of short-lived nuclear states with high precis ion and efficiency. The method is directly applicable to measurements on ra dioactive beams. In the conventional experiments, the beam and the Coulomb excited projectiles are stopped in a multi-layered target, while the lighte r target nuclei traverse the whole target and are detected around 0 degrees in coincidence with projectile gamma -rays. But even for low intensity rad ioactive beams, this technique would lead to an excessive accumulation of a ctivity in the target. A method is presented here, in which the beam passes through the target and a hole in the particle detector and is stopped in a downstream beam dump shielded from the detectors. A test was carried out o n the g factor of the 2(l)(+) state of Ti-50. (C) 2000 Elsevier Science B.V . All rights reserved.