Search results for " ionization"
showing 10 items of 621 documents
Production of molecular sideband radioisotope beams at CERN-ISOLDE using a Helicon-type plasma ion source
2013
In order to account for the increasing demand for strong molecular beams for nuclear physics experiments at ISOLDE, a new radioactive ion source concept based on an RE discharge in a magnetized plasma was developed at CERN. Experimental studies at the ISOLDE offline separator show that the optimum conditions for CO+ and CO2+ ion production are given when the ion source is operated with He plasma, in line with expectations based on their electron impact ionization cross-sections. At optimum tuning, ionization efficiencies of 2.5% and 4% were measured for CO+ and Ar+, respectively. The capability of the Helicon ion source prototype for ISOL operation was evaluated during two online runs at th…
Resonance ionization of holmium for ion implantation in microcalorimeters
2016
Abstract The determination of the electron neutrino mass by calorimetric measurement of the 163 Ho electron capture spectrum requires ultra-pure samples. Several collaborations, like ECHo or HOLMES, intend to employ microcalorimeters into which 163 Ho is implanted as an ion beam. This makes a selective and additionally very efficient ion source for holmium mandatory. For this purpose, laser resonance ionization of stable holmium 165 Ho was studied, using a three step excitation scheme driven by pulsed Ti:sapphire lasers. Five measurements with sample sizes of 10 14 and 10 15 atoms were performed for the efficiency investigation. In average, an excellent ionization efficiency of 32(5) % coul…
New developments of the in-source spectroscopy method at RILIS/ISOLDE
2013
At the CERN ISOLDE facility, long isotope chains of many elements are produced by proton-induced reactions in target materials such as uranium carbide. The Resonance Ionization Laser Ion Source (RILIS) is an efficient and selective means of ionizing the reaction products to produce an ion beam of a chosen isotope. Coupling the RILIS with modern ion detection techniques enables highly sensitive studies of nuclear properties (spins, electromagnetic moments and charge radii) along an isotope chain, provided that the isotope shifts and hyperfine structure splitting of the atomic transitions can be resolved. At ISOLDE the campaign to measure the systematics of isotopes in the lead region (Pb, Bi…
Inner shell ionization of argon in ECRIS plasma
2018
Abstract The volumetric K α emission rate of argon emitted from the electron cyclotron resonance (ECR) heated plasmas of the JYFL (University of Jyvaskyla, Department of Physics) 14 GHz ECR ion source (ECRIS) and the 14.5 GHz Grenoble Test Source (GTS) at iThemba Laboratory for Accelerator Based Sciences have been measured to gain an understanding of the influence of the ion source tune parameters on the absolute inner shell ionization rate. It was observed that the behaviour of the ionization rate and the extracted ion beam currents react differently, depending the parametric sweep performed. The neutral gas pressure and incident microwave power was found to have the strongest influence on…
Advances in surface ion suppression from RILIS: Towards the Time-of-Flight Laser Ion Source (ToF-LIS)
2016
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…
Resonance ionization mass spectroscopy for nuclear research and trace analysis
1987
Resonance ionization mass spectroscopy (RIMS) has been applied, firstly, to a study of the nuclear properties of short-lived Au isotopes at the on-line isotope separator ISOLDE at CERN and, secondly, to a trace-analysis experiment of Pu.
Laser resonance ionization for efficient and selective ionization of rare species
2003
Abstract Due to the steady development and refinement of powerful pulsed as well as continuous-wave lasers, resonance ionization has developed into an extremely versatile tool for numerous applications. Apart from suppressing isobaric interferences and contributing to isotopic selectivity already in the ionization process, resonant optical excitation and ionization with laser light ensures high overall efficiency and good temporal and spatial controls of the ions delivered to mass spectrometric applications. In the field of rare isotope research laser resonance ionization has nowadays become one of the key techniques, including similarly the determination of long-lived or stable ultra-trace…
The charge radii of $^{198}$Pt - $^{183}$Pt
1989
The changes of the mean-square charge radii have been measured for198Pt-183Pt by means of resonance ionization mass spectroscopy (RIMS) at the new on-line isotope separator ISOLDE-3/CERN. As in the case of the neighbouring isotopes of Au and Hg, a strong nuclear deformation of ¦β2¦ −-0.24 is reached at the neutron mid-shell nucleus183Pt, but no indication for a sharp shape transition is observed from the study of the isotope shifts.
Development of resonance ionization in a supersonic gas-jet for studies of short-lived and long-lived radioactive nuclei
2013
High-resolution resonance ionization spectroscopy (RIS) is required for laser spectroscopy and trace analysis of short-lived and long-lived radioactive nuclei. We have proposed high-resolution resonance ionization spectroscopy in a gas jet combined with a narrow band-width injection-locked Ti:Sapphire laser. Resonance ionization of stable 93Nb in a gas jet was demonstrated using a broad bandwidth Ti:Sapphire laser. In addition, a setup for high-resolution RIS in a gas-jet was designed using numerical simulations of the gas-jet conditions based on computational fluid dynamics.
In-source laser spectroscopy of dysprosium isotopes at the ISOLDE-RILIS
2019
A number of radiogenically produced dysprosium isotopes have been studied by in-source laser spectroscopy at ISOLDE using the Resonance Ionization Laser Ion Source (RILIS). Isotope shifts were measured relative to $^{152}$Dy in the 4 f$^{ 10}$6s$^{2}$ $^5$I$_8$ (gs) $\rightarrow$ 4 f$^{ 10}$6s6p (8,1)$^8_o$ (418.8 nm$_{vac}$) resonance transition. The electronic factor, F, and mass shift factor, M, were extracted and used for determining the changes in mean-squared charge radii for $^{145m}$Dy and $^{147m}$Dy for the first time. A number of radiogenically produced dysprosium isotopes have been studied by in-source laser spectroscopy at ISOLDE using the Resonance Ionization Laser Ion Source (…