Design status of KOBRA for rare isotope production and direct measurements of radiative capture cross sections

Abstract

KOBRA (KOrea Broad acceptance Recoil spectrometer and Apparatus) facility being designed at Rare Isotope Science Project in Korea will be utilized to produce rare isotope beams by employing multi nucleon transfer reactions at about 20 MeV/nucleon for studies of nuclear structure. KOBRA will also provide high suppression of beam induced background for direct measurements of radiative-capture cross sections in the astrophysical energy range. The present design status of the KOBRA facility is reported along with a brief introduction to the facility. We have studied the feasibility of production of Ti-44 based on the present design of KOBRA as an example, and calculated the intensity of Ti-44 secondary beam, to be about 105 particles per second, for 1 pnA Ti-46 primary beam with a carbon target for a beam energy of 25 MeV/nucleon. A Monte Carlo simulation with a ray-tracing code has been performed to show that recoil products Se-66 are well separated from a As-65 beam by KOBRA for the As-65(p, gamma)Se-66 reaction at a beam energy of 1 MeV/nucleon.