Gas-Filled Recoil Separator for Super-Heavy Nuclei

A new gas-filled recoil separator in HIRFL was introduced, which was dedicated to studies of the super-heavy nuclei. The configuration and technical parameters of the facility were described in detail. By using the complete fusion-evaporation reaction ¹⁷⁵Lu(⁴⁰Ar,4-5n)^211,210Ac, the charge state distributions of evaporation residues in helium gas were measured at the different pressures. Experimental equilibrium charge states in the present work were deduced, which were well coincided with the calculation of empirical formula. The transmission of the separator for Ac is 14% which should be considered as a lower limit.