High efficiency ISOL system to produce neutron deficient short-lived alkali RIBs on GANIL/SPIRAL 1 facility

Abstract The SPIRAL1 (Systeme de Production d’Ions Radioactifs Acceleres en Ligne) facility at GANIL ( Grand Accelerateur National d’Ions Lourds) is developing new techniques to access nuclei in the neutron-deficient isotope region far from the stability-valley, with Z ranging from 30 to 60. The availability of different primary beams, ranging from carbon to uranium with energies up to 95 MeV/A, gives an opportunity to produce a large variety of radioactive ion beams. The production of neutron-deficient short-lived alkalis by fusion-evaporation reactions is the focus of this work. A simple and compact target ion source system (TISS) is designed to produce isotopes of 74 Rb ( τ 1 / 2  = 64.8 ms) and 114 Cs ( τ 1 / 2  = 570 ms). The efficiencies of the different processes involved in the production are evaluated. Radioactive recoils are produced through the interaction of heavy-ion beams, respectively 20 Ne beam and 58 Ni beam at an intensity of 10 13 and 10 12 pps, with a thin 58 Ni target. High atom-to-ion transformation (ATI) efficiency should be obtained above 70% and 90% for 74 Rb and 114 Cs nuclei respectively. The expected intensities of the RIBs are estimated to be around 10 4 pps at the exit of the TISS.