Radioactive ion beam line in Lanzhou

Abstract

Radioactive ion beam line in Lanzhou (RIBLL) has been constructed for the production of short-lived radioactive nuclei and studies of exotic nuclei far from the β-stability line. It has been put into operation recently at the National Laboratory of Heavy Ion Accelerator Lanzhou. RIBLL consists of two doubly achromatic parts with a solid acceptance ΔΩ⩾6.5 msr, momentum acceptance Δp/p=±5% and maximum magnetic rigidityBp max=4.2 Tm. The second part of RIBLL serving as a spectrometer gives an element resolutionZ/ΔZ>150 and mass resolutionA/ΔA>300. The polarized secondary beams can be obtained by using a swinger dipole magnet to change the incident direction of primary projectile from 0° to 5°. The shortest lift time for secondary beams on RIBLL is less than 1 μs. First experiments were performed with neutron rich nuclei for understanding the properties of halo nuclei and exotic nuclear reactions.