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2.
Hartmut Backe 《Zeitschrift für Physik A Hadrons and Nuclei》1971,241(5):435-458
Absolute intensities of the 5–4 muonic X-ray transition in muonic W, Os, and Bi, and relative intensities of other X-ray transitions have been measured and compared with cascade calculations. The excitation of several levels in W, Os, Ir, Tl, and Bi nuclei resulting from the muonic cascade process has been observed and absolute excitation probabilities have been determined. For the first 2+ level of188Os and the first 3/2+-levels of203,205Tl the excitation probabilities are larger than calculated. The results are discussed. 相似文献
3.
P. J. Daly P. Kleinheinz R. Broda S. Lunardi H. Backe J. Blomqvist 《Zeitschrift für Physik A Hadrons and Nuclei》1980,298(3):173-185
The yrast states of148Dy and149Dy have been studied by γ-ray and conversion electron measurements in (α, xn) and (16O,xn) reactions on enriched152Gd and135Ce targets. Level schemes to above 4 MeV for the two nuclei are reported. The πh 2 11/2 spectrum identified in148Dy and the πh 11/2 effective chargee eff=1.52±0.05e, derived from the measuredE2 transition rate between the (πh 2 11/2) 10+ and 8+ states, are discussed and compared with results for other two-particle nuclei. The yrast cascades in148Dy and149Dy continue above the (πh 2 11/2) 10+ and πh 2 11/2 vf 7/2) 27/2? states by ~ 1 MeVE1 transitions de-exciting the lowest members of octupole multiplets built on these states. The energy shifts for the observed members of the πh 2 11/2 × 3? multiplet are analyzed in terms of twoparticle-phonon exchange coupling using an empirical coupling strength extracted from the one valence particle nucleus147Tb. The dominantvf 7/2×3? character of low-lying 13/2+ isomers in149Dy and otherN=83 nuclei is emphasized. 相似文献
4.
A. Dretzke H. Backe G. Kube W. Lauth W. Ludolphs A. Morbach M. Sewtz 《Hyperfine Interactions》2001,132(1-4):497-500
Heavy element chemistry is related to the fundamental interest that lies in exploring the upper limits of the periodic table.
Chemical properties of the heaviest elements have already been studied at single atoms in aqueous solutions and in the gas
phase up to an atomic number Z = 107. These techniques allow to study nuclides with half lives as short as about 1 s. Next generation chemistry experiments
could be envisaged with an ion trap technique already developed for stable isotopes. At very low production rates in the order
of 1 per 100 s and/or half lives as short as about 10 ms, the ion-molecule reactions can be studied in a buffer gas cell,
in which the heavy elements are stopped and thermalize with a high probability as singly charged ions. Ion-molecule reactions
with well defined buffer gas admixtures, as, e.g., O2, H2O, CH4, CO2, are identified by mass selective detection.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
G. Marx D. Ackermann J. Dilling F.P. Hessberger S. Hoffmann H.-J. Kluge R. Mann G. Münzenberg Z. Qamhieh W. Quint D. Rodriguez M. Schädel J. Schönfelder G. Sikler C. Toader C. Weber O. Engels D. Habs P. Thirolf H. Backe A. Dretzke W. Lauth W. Ludolphs M. Sewtz 《Hyperfine Interactions》2001,132(1-4):459-464
The ion trap facility SHIPTRAP is being set up to deliver very clean and cool beams of singly-charged recoil ions produced
at the SHIP velocity filter at GSI Darmstadt. SHIPTRAP consists of a gas cell for stopping and thermalizing high-energy recoil
ions from SHIP, an rf ion guide for extraction of the ions from the gas cell, a linear rf trap for accumulation and bunching
of the ions, and a Penning trap for isobaric purification. The progress in testing the rf ion guide is reported. A transmission
of about 93(5)% was achieved.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
6.
Ohne Zusammenfassung 相似文献
7.
H. Backe P. Graffé D. Habs M. Hies Ch. Illgner H. Kunz W. Lauth H. Schöpe P. Schwamb W. Theobald P. Thörle N. Trautmann R. Zahn 《Hyperfine Interactions》1993,78(1-4):35-45
An ultra-sensitive laser spectroscopic method has been developed for the hyperfine spectroscopy of short-lived isotopes far off stability produced by heavy ion induced nuclear reactions at very weak intensity (> 1/s). It is based on resonance ionization spectroscopy in a buffer gas cell with radiation detection of the ionization process (RADRIS). As a first on-line application of RADRIS optical spectroscopy at242fAm fission isomers is in progress at the low target production rate of 10/s. The resonance ionization has been performed in two steps utilizing an excimer dye laser combination with a repetition rate of 300 Hz. The first resonant step proceeds through terms which correspond to wavelengths of 466.28, 468.17 or 426.56 nm; the second non-resonant step is achieved with the 351 nm radiation of the excimer laser itself, running with XeF. The frequency scans of the tuneable dye laser at 466.28 and 468.17 nm exhibit broad resonance ionization signals, the latter with a large isotope shift between242fAm and243Am which is in accordance with the large quadrupole moment of the242fAm fission isomer.Work supported by the Bundesministerium für Forschung und Technologie under contract 06 MZ 188 I. 相似文献
8.
H. Backe A. Dretzke St. Fritzsche R. G. Haire P. Kunz W. Lauth M. Sewtz N. Trautmann 《Hyperfine Interactions》2005,162(1-4):3-14
The level scheme and hyperfine structure of the element fermium (Z = 100) has been investigated with the method of resonance ionization spectroscopy in a buffer gas cell. The experiments were
carried out on a 46 pg sample of the isotope 255Fm with a half-life time of 20.1 h, produced in the high flux nuclear reactor of the ORNL, Oak Ridge, USA. A wave number scan
from 27,100 to 28,400 cm−1 was carried through to search for three levels with large Einstein-coefficients, as predicted by ab initio Multi-Configuration-Dirac-Fock (MCDF) calculations, and five new levels were found. In addition, the two known levels at
wave numbers (25,099.8 ± 0.2) and (25,111.8 ± 0.2) cm−1 were studied with a laser band width of 1.5 GHz and hyperfine broadenings were observed. 相似文献
9.
H. Backe F. P. Heßberger M. Sewtz A. Türler 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,45(1):3-15
This article reviews the following topics which were discussed at the
375th Wilhelm and Else Heraeus-Seminar
Workshop on the Atomic Properties of the Heaviest Elements
held from September 25–27, 2006 at the Abtei Frauenw?rth im Chiemsee, Germany:
(i) the recent progress in the
production of the heaviest elements, the investigation of their
nuclear structure, and prospects for direct mass measurements in
Penning traps. (ii) Recent studies of their chemical
properties with the aid of volatile species and single-atom
aqueous-phase chemistry; (iii) the current status and future prospects for
the investigation of atomic and ionic properties such as
optical
spectroscopy in gas cells and ion traps, including fully
relativistic calculations of the atomic level structure with
predictions for the element nobelium; and (iv) ionic charge radii
measurements in buffer gas filled drift cells, and ion chemical
reactions in the gas phase. 相似文献
10.
M. Piiparinen S. Lunardi P. Kleinheinz H. Backe J. Blomqvist 《Zeitschrift für Physik A Hadrons and Nuclei》1979,290(3):337-338
Three yrast isomers in151Dy, at 6.03 MeV (I=49/2, T/=15(3) ns), 4.90 MeV (41/2?, 5.5(1.0) ns), and at 2.96 MeV(27/2?, 1.3(6) ns) have been located through152Gd(α,5n) and136Ce(18O, 3n) measurements. Shell model configurations are suggested for them. 相似文献