Laser resonance ionization mass spectroscopy of radioactive isotopes

“放射性同位素的激光共振电离质谱”项目旨在研究At、Ra、Ac和锕系元素的光学同位素变化趋势，其中许多元素以前没有被测量过。激光共振电离是一种灵敏度高、选择性强的痕量探测方法，可以探测基态核结构和长寿命同分异构体核结构。与放射性离子束设备相结合，可以获得大量特定元素的同位素，这种技术可以用来绘制核结构从稳定到滴线图的演变。核信息是通过探测原子核的原子电子的激光光谱学获得的。这种相互作用是一种敏感的、非破坏性的探测，它允许以一种很大程度上独立于模型的方式提取微妙的核效应。可测量的特殊核性质是：核自旋、磁偶极矩和电四极矩以及核链中特定元素同位素间均方根电荷半径的变化。在某些情况下，也可以提取高阶效应，如磁八极矩。***这项工作的结果影响了核物理学的各个领域，从核结构到锕系元素内部的基本对称性测试。***激光共振电离质谱计划的开发部分推进了技术和开发技术，使锕系元素的同位素在强度和纯度上更容易获得，以便通过核结构和高分辨率激光光谱进行后续的高分辨率研究。未来几年的重点是改进“离子引导激光离子源”，并利用脉冲激光源的共振电离技术的时间结构。这将允许系统地研究砹、镭和锕系元素的同位素链。***要求的资金用于支付最多2名研究生（1名博士和1名硕士）的津贴以及他们在本国机构的教学所需的买断费。此外，参加会议和合作会议的差旅费也包括在内。***在加拿大境内，这是马尼托巴大学和TRIUMF之间的合作。在国际范围内，与美因茨大学、奥尔登堡大学、埃姆登/利尔应用科学大学、鲁汶大学以及CERN-ISOLDE（瑞士）、GANIL（法国）和JYFL（芬兰）有着密切的合作，其中包括频繁的学生交流和合作发展。

The program in "Laser resonance ionization mass spectrometry of radioactive isotopes" seeks to investigate trends in the optical isotope shifts in isotopes of At, Ra, Ac, and the actinide elements many of which have not been measured before. Laser resonance ionization has emerged as a highly sensitive and selective method in trace detection, which also allows to probe nuclear structure of ground state and long lived isomeric states of atomic nuclei. In combination with radioactive ion beam facilities that give access to a great number of isotopes of particular elements, this technique can be used to map the evolution of nuclear structure from stability out to the drip lines. The nuclear information is accessed via laser spectroscopy of the atomic electrons that probe the nucleus. This interaction is a sensitive, non-destructive probe that allows to extract subtle nuclear effects in a largely model independent way. The particular nuclear properties measureable are: nuclear spin, magnetic dipole and electric quadrupole moments and changes in the root mean square charge radii among isotopes of a specific element in a nuclear chain. In some cases higher order effects such as magnetic octupole moments can be extracted as well. ***The results of this work impact areas of nuclear physics from nuclear structure to fundamental symmetry tests within the actinides. ***The development portion of laser resonance ionization mass spectrometry program advances technology and develops techniques to make isotopes of the actinide elements more accessible both in intensity as well as purity for subsequent high resolution studies by nuclear structure and high resolution laser spectroscopy. The focus for the coming years is to refine an “ion-guide laser ion source” and to capitalize on the time structure of our resonance ionization technique with pulsed laser sources. This will allow for the systematic investigation of isotope chains in astatine, radium and the actinides.***The funds requested are to cover the stipend of up to 2 graduate students (1 Ph.D. and 1 M.Sc.) as well as the required buyout of their teaching at their home institutions. In addition travel cost associated with both conference attendance and collaboration meetings are included. ***Within Canada this is a collaboration between the University of Manitoba and TRIUMF. On an international scale there exists a strong collaboration with the University of Mainz, the University Oldenburg, University of Applied Sciences Emden/Leer, KU Leuven on the University side, and CERN-ISOLDE (Switzerland), GANIL (France) and JYFL (Finnland) which includes frequent exchange of students and collaborative developments.