Rotating target facility for in-flight radioactive ion beam production using a recoil mass spectrometer

Abstract

A facility has been developed for production of light radioactive ion beams (RIBs) using (p,n), (d,n) reactions in inverse kinematics using an in-flight technique. Primary beams from the 15UD Pelletron accelerator are used on a hydrogenous target and the RIB is separated and re-focused to a secondary target position using the existing recoil mass spectrometer (RMS), HIRA operated in a new ion-optical configuration. To satisfy the ion-optical requirement of a well-defined object spot-size, we opted for polypropylene foil targets instead of hydrogen gas. As these foils get rapidly damaged with beam irradiation, a new design has been used to fabricate a rotary/linear motion device. This design allows the utilization of large area foils as production targets. It also, intrinsically, avoids scattering of primary beam from unwanted materials, which is crucial for beam rejection with an RMS operating at zero degrees. In this paper we present the details of the design and beam test results.