Thursday, May 08, 2025, 16:00
WHGA Auditorium
Klaus Wendt, Mainz University
Abstract:
The resonance ionization laser ion sources RILIS, pioneered by V.S.
Letokhov and his group in the 1980ties, have since found wide
applications at all on-line isotope separator facilities worldwide. This
success is based on the excellent specifications of ultimate ionization
efficiency, realized for most elements of the periodic table, combined
with very high selectivity achieved by suppressing unwanted isobars to a
minimum in the ionization process.
The advent of tunable lasers with high power, high repetition rate and
easy operation, which cover the entire spectral range from UV to far IR
and which can universally be adapted to individual atomic spectra and
scientific tasks, has led to further superb progress in this field in
recent decades. In addition to the efficient production of pure ion
beams of radioisotopes for fundamentals studies or nuclear medicine,
e.g. at the CERN radioactive beam facilities (RIB) ISOLDE (on-line) or
MEDICIS (off-line), or the collection of ultrapure radioisotope samples
as calibration sources, carried out e.g. at the RISIKO off-line RIB at
University of Mainz, meaningful optical spectroscopy within the laser
ion source unit has become possible. By adequate design of the
laser-atom interaction region and adaptation of the laser
specifications, high-resolution spectroscopy has been demonstrated. In
this way the basic tasks of ion beam generation or studies on atomic
physics data of rare species today is complemented by direct
measurements of nuclear ground state properties extracted from optical
hyperfine structures and isotope shifts. An overview on the present
status of the RILIS technique covering recent developments on ion source
units and laser optimizations will be given together with examples on
applications in rare radioisotope purification or fundamental
spectroscopy along the periodic table from 53Mn up to
257Fm.