Towards commissioning the new IGISOL-4 facility Moore, I.D.; Eronen, T.; Gorelov, D. ...
Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms,
12/2013, Letnik:
317
Journal Article
Recenzirano
•The commissioning of the new IGISOL-4 facility.•First successful implantation of neutron-deficient Pd.•In-jet laser ionization of copper demonstrated.
The Ion Guide Isotope Separator On-Line ...facility at the Accelerator Laboratory of the University of Jyväskylä is currently being re-commissioned as IGISOL-4 in a new experimental hall. Access to intense beams of protons and deuterons from a new MCC30/15 cyclotron, with continued possibility to deliver heavy-ion beams from the K=130MeV cyclotron, offers extensive opportunities for long periods of fundamental experimental research, developments and applications. A new layout of beam lines with a considerable increase in floor space offers new modes of operation at the facility, as well as a possibility to incorporate more complex detector setups. We present a general overview of IGISOL-4 and the current status of several projects, including the collinear laser spectroscopy station and the future of neutron-induced fission. Recent milestones from the first commissioning experiments are presented.
Resonant laser ionization and spectroscopy are widely used techniques at radioactive ion beam facilities to produce pure beams of exotic nuclei and measure the shape, size, spin and electromagnetic ...multipole moments of these nuclei. However, in such measurements it is difficult to combine a high efficiency with a high spectral resolution. Here we demonstrate the on-line application of atomic laser ionization spectroscopy in a supersonic gas jet, a technique suited for high-precision studies of the ground- and isomeric-state properties of nuclei located at the extremes of stability. The technique is characterized in a measurement on actinium isotopes around the N=126 neutron shell closure. A significant improvement in the spectral resolution by more than one order of magnitude is achieved in these experiments without loss in efficiency.
This article presents a pulsed narrowband injection-locked Titanium:Sapphire laser aimed for high-resolution in-jet resonance ionization spectroscopy at the SLOWRI/PALIS at RIKEN. The laser has been ...integrated into the PALIS laser laboratory enabling it to be utilized with the existing broadband Titanium:Sapphire and dye lasers. The seed efficiency has been evaluated to be close to unity over the master laser wavelength range ∼ 753 to 791 nm, and the slope efficiency, namely the ratio of the pump power to the output power, was determined to be ∼ 30 % at 780 nm. A two-step ionization scheme with 386.4016 nm first step and 286.731 nm second step into an autoionizing state was developed for resonance ionization spectroscopy of 93Nb. Magnetic hyperfine coupling constants of 1866±8 MHz and 1536±7 MHz were measured for the ground and excited state, respectively, in a good agreement with the literature values. A Gaussian dominated Voigt linewidth of 434.5 ± 7.4 MHz was extracted from the hyperfine spectra measured for niobium. In addition, the resolution of the in-jet resonance ionization in PALIS is estimated through numerical methods.
In-gas-cell resonance laser ionization has been performed on long-lived isotopes of Pu at the IGISOL facility, Jyväskylä. This initiates a new programme of research towards high-resolution optical ...spectroscopy of heavy actinide elements which can be produced in sufficient quantities at research reactors and transported to facilities elsewhere. In this work a new gas cell has been constructed for fast extraction of laser-ionized elements. Samples of 238–240,242Pu and 244Pu have been evaporated from Ta filaments, laser ionized, mass separated and delivered to the collinear laser spectroscopy station. Here we report on the performance of the gas cell through studies of the mass spectra obtained in helium and argon, before and after the radiofrequency quadrupole cooler-buncher. This provides valuable insight into the gas phase chemistry exhibited by Pu, which has been additionally supported by measurements of ion time profiles. The resulting monoatomic yields are sufficient for collinear laser spectroscopy. A gamma-ray spectroscopic analysis of the Pu samples shows a good agreement with the assay provided by the Mainz Nuclear Chemistry department.
The laser and optical system for the RIBF-PALIS experiment Sonoda, T.; Iimura, H.; Reponen, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2018, Letnik:
877
Journal Article
Recenzirano
This paper describes the laser and optical system for the Parasitic radioactive isotope (RI) beam production by Laser Ion-Source (PALIS) in the RIKEN fragment separator facility. This system requires ...an optical path length of 70 m for transporting the laser beam from the laser light source to the place for resonance ionization. To accomplish this, we designed and implemented a simple optical system consisting of several mirrors equipped with compact stepping motor actuators, lenses, beam spot screens and network cameras. The system enables multi-step laser resonance ionization in the gas cell and gas jet via overlap with a diameter of a few millimeters, between the laser photons and atomic beam. Despite such a long transport distance, we achieved a transport efficiency for the UV laser beam of about 50%. We also confirmed that the position stability of the laser beam stays within a permissible range for dedicated resonance ionization experiments.
Recommissioning of JYFLTRAP at the new IGISOL-4 facility Kolhinen, V.S.; Eronen, T.; Gorelov, D. ...
Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms,
12/2013, Letnik:
317, Številka:
Part B
Journal Article
Recenzirano
•The JYFLTRAP system has been moved to a new location and commissioned.•The line between RFQ and the Penning traps allows implementation of extra devices.•The RFQ cooler/buncher and both Penning ...traps are operational.•The buffer-gas cooling method and the excitations in the purification trap works.•TOF-ICR technique in the precision trap works. A resonance picture shown.
The JYFLTRAP double Penning-trap system was moved to a new location along with the Ion Guide Isotope Separator On-line (IGISOL) facility at the Accelerator Laboratory of the University of Jyväskylä. The move made it possible to upgrade various parts of the facility. For example, separate beam lines for JYFLTRAP and the collinear laser spectroscopy station were constructed after the radio-frequency quadrupole cooler and buncher. In this contribution we give an overview of the new JYFLTRAP facility and results from the first stable ion-beam tests.
PDF
