Laser resonance ionization techniques for studying the properties of unstable nuclei

Abstract

The fundamental properties of unstable nuclei are highly related to the nuclear structure and effective nucleon-nucleon interaction, and they can be used to study various exotic structures of unstable nuclei. Laser spectroscopy is a powerful tool used to study nuclear properties and structure by probing the hyperfine structure and isotope shift of the corresponding atoms or ions, from which the nuclear properties can be extracted in a nuclear model-independent manner. Multi-step laser resonance ionization spectroscopy (RIS) can be used to measure the atomic or ionic hyperfine structure. Based on this approach, various experimental techniques have been developed at radioactive ion beam (RIB) facilities worldwide to study the nuclear properties and structure of atomic nuclei. In this paper, the RIS approaches and relevant RIS experimental techniques are first introduced. Subsequently, the recently-developed collinear resonance ionization spectroscopy experimental technique, which can be used to measure the atomic or ionic hyperfine structure spectrum with a high-resolution and high sensitivity and plays an important role in the study of the nuclear properties and structure of unstable nuclei in the large mass regions of nuclear charts, is discussed in detail. Finally, the development status of RIS and its application in domestic RIB facilities are discussed.

Keywords

• unstable nuclei
• hyperfine structure
• laser resonance ionization
• laser spectroscopy technique