0000000000077033
AUTHOR
B. Crepieux
On-line implementation and first operation of the Laser Ion Source and Trap at ISOLDE/CERN
13 pags.; 12 figs.; 2 tab.; Open Access funded by CERN
Advances in surface ion suppression from RILIS: Towards the Time-of-Flight Laser Ion Source (ToF-LIS)
Abstract We present results from the development towards the Time-of-Flight Laser Ion Source (ToF-LIS) aiming for the suppression of isobaric contaminants through fast beam gating. The capability to characterize high resistance ion sources has been successfully demonstrated. A ninefold selectivity gain has been achieved through suppression of surface ionized potassium, while maintaining >90% transmission for laser-ionized gallium using a thin wall graphite ionizer cavity combined with a fast beam gate. Initial results from the investigation of glassy carbon as a potential hot cavity ion source are presented. Power-cycle tests of a newly designed mount for fragile ion source cavities indicat…
Very high specific activity erbium 169Er production for potential receptor-targeted radiotherapy
Erbium 169Er is one of the most interesting radiolanthanides for new potential receptor-targeted β− therapy applications due to its low energy β− emissions, very low intensity ɣ rays and the possibility to use 68Ga or 44Sc as companion for diagnostic in a theranostics approach. Currently it can be produced in reactors through the neutron activation of highly enriched 168Er. The low specific activity of the produced carrier-added 169Er is limiting its use for receptor-targeted therapy. Nonetheless it is used for radiosynoviorthesis of small joints. The aim of this work is to develop a new large-scale production method for the supply of very high specific activity 169Er. Highly enriched 168Er…
Enhancing the extraction of laser-ionized beams from an arc discharge ion source volume
© 2018 The Author(s) The Versatile Arc Discharge and Laser Ion Source (VADLIS) is a recently established ion source for the CERN-ISOLDE radioactive ion beam facility. It offers either electron-impact ionization (VADIS-mode) or resonance laser ionization (RILIS-mode). The choice of operating mode depends on the element of interest or the required beam purity. Particle-in-cell simulations using the VSim software show that the ion extraction efficiency of the VADLIS in RILIS-mode can be improved if it is equipped with an insulated extractor plate, to which an optimal voltage can be applied. This enables optimization of the RILIS-mode ion extraction independently of the electron density. Experi…
The LIEBE high-power target: Offline commissioning results and prospects for the production of 100Sn ISOL beams at HIE-ISOLDE
Abstract With the aim of increasing the primary beam intensity in the next generation Radioactive Ion Beam facilities, a major challenge is the production of targets capable of dissipating high beam power, particularly for molten targets. In that context, a direct molten loop target concept was proposed for short-lived isotopes for EURISOL. The circulation of molten metal enables the production of droplets enhancing the radioisotope diffusion. The concept also includes a heat exchanger ensuring thermal equilibrium under interaction with high proton beam power. A target prototype, named LIEBE, has been designed and assembled to validate this concept in the ISOLDE operation environment. The p…
The laser ion source trap for highest isobaric selectivity in online exotic isotope production
The improvement in the performance of a conventional laser ion source in the laser ion source and trap (LIST) project is presented, which envisages installation of a repeller electrode and a linear Paul trap/ion guide structure. This approach promises highest isobaric purity and optimum temporal and spatial control of the radioactive ion beam produced at an online isotope separator facility. The functionality of the LIST was explored at the offline test separators of University of Mainz (UMz) and ISOLDE/CERN, using the UMz solid state laser system. Ionization efficiency and selectivity as well as time structure and transversal emittance of the produced ion beam was determined. Next step aft…
Blurring the boundaries between ion sources: The application of the RILIS inside a FEBIAD type ion source at ISOLDE
For the first time, the laser resonance photo-ionization technique has been applied inside a FEBIAD-type ion source at an ISOL facility. This was achieved by combining the ISOLDE RILIS with the ISOLDE variant of the FEBIAD ion source (the VADIS) in a series of off-line and on-line tests at CERN. The immediate appli- cations of these developments include the coupling of the RILIS with molten targets at ISOLDE and the introduction of two new modes of FEBIAD operation: an element selective RILIS mode and a RILIS + VADIS mode for increased efficiency compared to VADIS mode operation alone. This functionality has been demonstrated off-line for gallium and barium and on-line for mercury and cadmi…
Study of Low Work Function Materials for Hot Cavity Resonance Ionization Laser Ion Sources
The selectivity of a hot cavity resonance ionization laser ion source (RILIS) is most often limited by contributions from competing surface ionization on the hot walls of the ionization cavity. In this article we present investigations on the properties of designated high-temperature, low-work function materials regarding their performance and suitability as cavity material for RILIS. Tungsten test cavities, impregnated with a mixture of barium oxide and strontium oxide (BaOSrO on W), or alternatively gadolinium hexaboride (GdB6) were studied in comparison to a standard tungsten RILIS cavity as being routinely used for hot cavity laser ionization at ISOLDE. Measurement campaigns took place …