Off-line study of a laser ion source via direct ionization at the He-jet outlet

A laser ion source based on laser resonant ionization (RI) at the He-jet outlet was proposed for the ISOL (on-line isotope separator) of HIRFL (Heavy Ion Research Facility in Lanzhou, China) a few years ago
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. An off-line test setup was built at Tsinghua University, Beijing. Initial experimental results indicate that carrying neutral Na monoatoms to the He-jet outlet and then using laser resonant ionization of Na atoms in the He-jet beam are very efficient. This provides a highly efficient method for producing Z selected ions with low background and short delay time. This method is useful in the separation of various elements, particularly, refractory elements.