Speaker
Description
The Resonance ionization spectroscopy And Purification Traps for Optimized spectroscopy (RAPTOR) project is a new experimental setup located at the Ion Guide Separator On-Line (IGISOL) laboratory in the Department of Physics of the University of Jyväskylä. RAPTOR combines the two most common methods for laser spectroscopy in use at radioactive ion beam facilities: collinear laser spectroscopy and in-source laser-resonance ionization spectroscopy, resulting in perhaps the most promising approach for optical spectroscopy by exploiting the high selectivity of resonance laser ionization, the high efficiency of ion detection, and the high resolution permitted using fast beams. This technique, collinear resonance ionization spectroscopy (CRIS) [1], was pioneered in the past decade at the Isotope Separator On-Line Device (ISOLDE) at the European Organization for Nuclear Research (CERN).
While the conventional collinear laser spectroscopy and CRIS methods exploit the kinematic compression of Doppler-broadening effects with beam energies of 30-60 keV, the RAPTOR device uniquely employs beam energies of only a few keV. Although the lower beam energy leads to somewhat lower spectral resolution, it allows for the improvement of the charge-exchange efficiency in the neutralization process, as the probability to neutralize into a specific atomic state increases when the beam energy decreases, also increasing the selectivity of the process. Measurements requiring high efficiency, for example the short-lived bismuth isotopes, are thus uniquely suitable for RAPTOR as the energy of the ions can be optimized to suit the optimum charge-exchange requirements and enables the study of many outstanding physics cases using exotic isotopes that are challenging to produce with traditional ISOL-type facilities.
My contribution will present the technical details and planned upgrades of the RAPTOR device. Recent results from ongoing commissioning tests, such like first RIS spectra from stable copper and ion beam transport simulations will also be presented.
References
[1] A. R. Vernon, et al. “Optimising the Collinear Resonance Ionization Spectroscopy (CRIS) Experiment at CERN-ISOLDE.” Nuclear Instruments & Methods In Physics Research Section B-Beam Interactions With Materials And Atoms, vol. 463, 2020, pp. 384–389.
