Search results for "IGISOL"
showing 10 items of 23 documents
Fission yield measurements at IGISOL
2016
The fission product yields are an important characteristic of the fission process. In fundamental physics, knowledge of the yield distributions is needed to better understand the fission process. For nuclear energy applications good knowledge of neutroninduced fission-product yields is important for the safe and efficient operation of nuclear power plants. With the Ion Guide Isotope Separator On-Line (IGISOL) technique, products of nuclear reactions are stopped in a buffer gas and then extracted and separated by mass. Thanks to the high resolving power of the JYFLTRAP Penning trap, at University of Jyväskylä, fission products can be isobarically separated, making it possible to measure rela…
Precision measurement of the half-life and the decay branches of 62Ga
2005
In an experiment performed at the Accelerator Laboratory of the University of Jyvaskyla, the beta-decay half-life of 62Ga has been studied with high precision using the IGISOL technique. A half-life of T1/2 = 116.09(17)ms was measured. Using beta-gamma coincidences, the gamma intensity of the 954keV transition and an upper limit of the beta-decay feeding of the 0+_2 state have been extracted. The present experimental results are compared to previous measurements and their impact on our understanding of the weak interaction is discussed.
Improved ion guide for heavy-ion fusion-evaporation reactions
1998
The ion guide for heavy-ion-induced reactions developed originally for the SARA facility in Grenoble has been implemented at the Jyvaskyla IGISOL facility. For the Cd-116(Ar-40, 6n)Dy-150 reaction an efficiency of 0.5% relative to the number of reaction products entering the stopping chamber was obtained. This is 3.5 times higher than previously obtained at SARA and corresponds to a yield of about 100 ions/(p mu C mb). Mass-separated yields for the Ar-36 + Mo-92 and Ar-36 + Mo-94 reactions were measured. (C) 1998 Elsevier Science B.V. All rights reserved.
Total Absorption Spectroscopy of Fission Fragments Relevant for Reactor Antineutrino Spectra Determination
2015
8 pags., 3 figs., 1 tab. ; Presented at the XXXIV Mazurian Lakes Conference on Physics, Piaski, Poland, September 6–13, 2015.
Fabry-Pérot Interferometer : construction, calibration and developement
2015
The work presented in this thesis concentrates on the construction and development of a Fabry-Perot Interferometer (FPI). Resonance ionization spectroscopy (RIS) is a powerful technique for the extraction of nuclear structure, namely nuclear spins, moments and changes in mean-square charge radii. However, due to the pulsed nature of the laser, the technique may be limited by the laser linewidth to low resolution spectroscopy. This thesis presents the construction and characterization of a Fabry-Perot Interferometer in order to measure the laser linewidth and to calibrate the wavelength of a pulsed Ti:Sapphire laser in "Narrowband" mode (<1 GHz). The FPI has been directly utilized in the mea…
A new off-line ion source facility at IGISOL
2019
An off-line ion source station has been commissioned at the IGISOL (Ion Guide Isotope Separator On-Line) facility. It offers the infrastructure needed to produce stable ion beams from three off-line ion sources in parallel with the radioactive ion beams produced from the IGISOL target chamber. This has resulted in improved feasibility for new experiments by offering reference ions for Penning-trap mass measurements, laser spectroscopy and atom trap experiments.
Low-spin excitations in 89Br populated in β−decay of 89Se
2022
Low-spin, excited states of the 89Br nucleus, populated in β− decay of 89Se have been studied for the first time. The 89Se nuclei were produced in proton-induced fission of natural thorium using the IGISOL facility and separated using a dipole magnet and the coupled JYFLTRAP Penning trap. Gamma radiation following the β− decay of 89Se was measured with an array of high-resolution germanium detectors. Levels scheme of 89Br was extended by 12 new levels and 31 new γ transitions. Spin-parity (3/2+) has been proposed for the ground state of the 89Se mother nucleus, replacing the (5/2+) assignment reported in data bases. The observed Gamow-Teller β− transition to the 1754.5-keV level indicates a…
Fission yield studies with SPIG-equipped IGISOL : a novel method for nuclear data measurements
2010
This thesis work consists of two sections. In the first section, the development of a so-called Laser Ion Source Trap (LIST) device is described. The LIST device is based on a double SPIG (SextuPole Ion Guide) system, providing the possibility to improve the elemental selectivity of the IGISOL method via highly discriminative laser ionization occurring outside the ion guide. The improved selectivity enables the production of isotopically pure beams. The double SPIG can be used without laser ionization and replaces the conventional skimmer electrode. In this work, the SPIG is compared to the skimmer and is shown to remarkably improve both the efficiency and beam quality of the IGISOL facilit…
Ion yields in HIGISOL experiments based on JYFLTRAP data and PACE4 simulations : based on JYFLTRAP data and PACE4 simulations
2012
The purpose of this thesis was to calculate ion yields in the neutron-deficient mass region A=78-111 in heavy-ion ion-guide experiments at the Ion Guide Isotope Separator On-Line (IGISOL) facility in the Accelerator Laboratory of the University of Jyväskylä. The biggest challenge was that the experiments were not designed for yield calculations but for precision mass measurements. Therefore, only a small fraction of the available data could be used. The results were compared to theoretical cross sections calculated with PACE4 code. Ion yields agreed roughly with the cross-section calculations: On the one hand, the ions with the highest cross sections were detected. On the other hand, ratios…