Search results for "Trap"
showing 10 items of 2144 documents
A highly selective laser ion source for bunched, low emittance beam release
2004
A novel type of resonance ionization laser ion source (RILIS) is under development, which combines the advantages of laser ionization with those of a source-implemented ion trap. This laser ion source trap (LIST) system, based on a gas-filled linear radio-frequency quadrupole ion trap, decouples the evaporation and ionization process by introduction of a primary surface ion repeller. Apart from significantly enhancing the selectivity in radioactive ion beam production, optimum control on the temporal pulse structure and the emittance of the generated laser ion bunch is obtained. A variety of operational modes from quasi-dc to microseconds-bunched ion beams with variable repetition rate can …
On the resonant neutrinoless double-electron-capture decay of ^{136}Ce
2011
Abstract The double-electron-capture Q value for the 136Ce decay to 136Ba has been determined at JYFLTRAP. The measured value 2378.53(27) keV excludes the energy degeneracy with the 0 + excited state of the decay daughter 136Ba at 2315.32(7) keV in a resonant 0 ν ECEC decay by 11.67 keV. The new Q value differs from the old adopted value 2419(13) keV (Atomic Mass Evaluation 2003) by 40 keV and is 50 times more precise. Our calculations show that the precise Q value renders the resonant 0 ν ECEC decay of 136Ce undetectable by the future underground detectors. We measured also the double-β decay Q value of 136Xe to be 2457.86(48) keV which agrees well with the value 2457.83(37) keV measured a…
Direct mass measurements of unstable rare earth isotopes with the ISOLTRAP mass spectrometer
1996
Abstract Direct mass measurements of neutron deficient rare earth isotopes in the vicinity of 146 Gd were performed for the first time with the Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN. Since ISOL-facilities deliver these isotopes with a large amount of isobaric contamination, these measurements became possible only after the installation of a new cooler trap which acts as an isobar separator. To date more than 40 isotopes of the elements Pr, Nd, Pm, Sm, Eu, Dy, and Ho have been measured with a typical accuracy of δm ≈ 14 keV. Some of these isotopes provide an important anchor for many other isotopes linked by known Q-values.
Accurate mass measurements on neutron-deficient krypton isotopes
2006
soumis à Nuclear Physics A; The masses of $^{72-78,80,82,86}$Kr were measured directly with the ISOLTRAP Penning trap mass spectrometer at ISOLDE/CERN. For all these nuclides, the measurements yielded mass uncertainties below 10 keV. The ISOLTRAP mass values for $^{72-75}$Kr outweighed previous results obtained by means of other techniques, and thus completely determine the new values in the Atomic-Mass Evaluation. Besides the interest of these masses for nuclear astrophysics, nuclear structure studies, and Standard Model tests, these results constitute a valuable and accurate input to improve mass models. In this paper, we present the mass measurements and discuss the mass evaluation for t…
High-accuracy mass determination of neutron-rich rubidium and strontiumiIsotopes
2002
The penning-trap mass spectrometer ISOLTRAP, installed at the on-line isotope separator ISOLDE at CERN, has been used to measure atomic masses of $^{88,89,90m,91,92,93,94}$Rb and $^{91- 95}$Sr. Using a resolving power of R $\!\scriptstyle\approx$1 million a mass accuracy of typically 10 keV was achieved for all nuclides. Discrepancies with older data are analyzed and discussed, leading to corrections to those data. Together with the present ISOLTRAP data these corrected data have been used in the general mass adjustment.
High-accuracy mass measurements of neutron-rich Kr isotopes
2006
The atomic masses of the neutron-rich krypton isotopes {sup 84,86-95}Kr have been determined with the tandem Penning trap mass spectrometer ISOLTRAP with uncertainties ranging from 20 to 220 ppb. The masses of the short-lived isotopes {sup 94}Kr and {sup 95}Kr were measured for the first time. The masses of the radioactive nuclides {sup 89}Kr and {sup 91}Kr disagree by 4 and 6 standard deviations, respectively, from the present Atomic-Mass Evaluation database. The resulting modification of the mass surface with respect to the two-neutron separation energies as well as implications for mass models and stellar nucleosynthesis are discussed.
Precision mass measurements of neutron-rich yttrium and niobium isotopes
2007
Abstract The atomic masses of neutron-rich 95–101 Y and 101–107 Nb produced in proton-induced fission of uranium were determined using the JYFLTRAP double Penning trap setup. Accuracies of better than 10 keV could be reached for most nuclides. The masses of 106,107 Nb were measured for the first time. The energies of the isomeric states in 96 Y and 100 Y were measured as 1541(10) keV and 145(15) keV. The niobium isotopes appear to be systematically less bound than the values given in the latest Atomic Mass Evaluation. The new data lie in a region of the nuclear chart characterised by the transition from spherical to strongly deformed shapes. These structural changes are explored by studying…
Penning trap at IGISOL
2002
The IGISOL facility [1] at the Department of Physics of the University of Jyvaskyla (JYFL) is delivering radioactive beams of short-lived exotic nuclei, in particular the neutron-rich isotopes from fission reaction. These nuclei are studied with the nuclear and collinear laser spectroscopy methods. In order to obtain a meaningful increase, in comparison to a standard level, of precision and sensitivity of such studies an improvement of the radioactive beam quality is necessary. This improvement will be achieved due to a radioactive beam handling which consists of three steps: beam cooling, bunching and (isobaric) purification. The latter means a possibility of obtaining a pure monoisotopic …
Direct mass measurements of neutron-rich zirconium isotopes up toZr104
2004
Atomic masses of radioactive zirconium isotopes from {sup 96}Zr to {sup 104}Zr have been measured with a relative accuracy of {<=}5x10{sup -7} using a Penning trap coupled to the ion guide isotope separator on-line system. The obtained two-neutron separation energies show strong local correlation in relation to the shape change and shape coexistence between N=58 and 60.
Hyperfine structure andg-factor measurements in ion traps
1992
We report about measurements on ground-state hyperfine splitting constants of stable Eu+ isotopes in radio frequency ion traps and experiments on the electronicg-factor of Ba+ in a Penning trap. From the precision of both measurements, which ranges between 3·10−6 and 5·10−7, we conclude that precise determination of the differential Bohr-Weisskopf effect in chains of isotopes will be possible in the near future.