학술논문
In-Source Laser Spectroscopy with the Laser Ion Source and Trap: First Direct Study of the Ground-State Properties of ^{217,219}Po
Document Type
article
Author
D. A. Fink; T. E. Cocolios; A. N. Andreyev; S. Antalic; A. E. Barzakh; B. Bastin; D. V. Fedorov; V. N. Fedosseev; K. T. Flanagan; L. Ghys; A. Gottberg; M. Huyse; N. Imai; T. Kron; N. Lecesne; K. M. Lynch; B. A. Marsh; D. Pauwels; E. Rapisarda; S. D. Richter; R. E. Rossel; S. Rothe; M. D. Seliverstov; A. M. Sjödin; C. Van Beveren; P. Van Duppen; K. D. A. Wendt
Source
Physical Review X, Vol 5, Iss 1, p 011018 (2015)
Subject
Language
English
ISSN
2160-3308
Abstract
A Laser Ion Source and Trap (LIST) for a thick-target, isotope-separation on-line facility has been implemented at CERN ISOLDE for the production of pure, laser-ionized, radioactive ion beams. It offers two modes of operation, either as an ion guide, which performs similarly to the standard ISOLDE resonance ionization laser ion source (RILIS), or as a more selective ion source, where surface-ionized ions from the hot ion-source cavity are repelled by an electrode, while laser ionization is done within a radio-frequency quadrupole ion guide. The first physics application of the LIST enables the suppression of francium contamination in ion beams of neutron-rich polonium isotopes at ISOLDE by more than 1000 with a reduction in laser-ionization efficiency of only 20. Resonance ionization spectroscopy is performed directly inside the LIST device, allowing the study of the hyperfine structure and isotope shift of ^{217}Po for the first time. Nuclear decay spectroscopy of ^{219}Po is performed for the first time, revealing its half-life, α-to-β-decay branching ratio, and α-particle energy. This experiment demonstrates the applicability of the LIST at radioactive ion-beam facilities for the production and study of pure beams of exotic isotopes.