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131.
G. Rouleau H. Borgenstrand C. Carlberg R. Schuch F. Söderberg I. Bergström R. Jertz T. Schwarz J. Stein G. Bollen H. -J. Kluge R. Mann 《Hyperfine Interactions》1996,99(1):73-81
Described in this paper is an experimental facility which measures atomic masses by using multiply charged ions from an electron beam ion source. The ions are injected into a Penning trap and the cyclotron frequencies measured. A precision of 2×10–9 has been reached using highly charged carbon, nitrogen, oxygen and neon. 相似文献
132.
M. Block D. Ackermann K. Blaum A. Chaudhuri Z. Di S. Eliseev R. Ferrer D. Habs F. Herfurth F. P. Heßberger S. Hofmann H.-J. Kluge G. Maero A. Martín G. Marx M. Mazzocco M. Mukherjee J. B. Neumayr W. R. Plaß W. Quint S. Rahaman C. Rauth D. Rodríguez C. Scheidenberger L. Schweikhard P. G. Thirolf G. Vorobjev C. Weber 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,45(1):39-45
The Penning-trap mass spectrometer SHIPTRAP allows precision mass
measurements of rare isotopes produced in fusion-evaporation reactions. In
the first period of operation the masses of more than 50 neutron-deficient
radionuclides have been measured.
In this paper the perspectives for direct mass measurements
of rare isotopes around nobelium are discussed and the achievable precision is addressed.
The temporal stability of the magnetic field, an important issue for the long
measurement times resulting from the low production rates, was investigated and the
time-dependent uncertainty due to magnetic field fluctuations was determined.
Based on the present performance direct mass measurements of nobelium isotopes are
already feasible. With several technical improvements heavier elements between Z=102–105 will be in reach. 相似文献
133.
A. Martın D. Ackermann G. Audi K. Blaum M. Block A. Chaudhuri Z. Di S. Eliseev R. Ferrer D. Habs F. Herfurth F. P. Heßberger S. Hofmann H. -J. Kluge M. Mazzocco M. Mukherjee J. B. Neumayr Yu. Novikov W. Plaß S. Rahaman C. Rauth D. Rodrıguez C. Scheidenberger L. Schweikhard P. G. Thirolf G. Vorobjev C. Weber 《The European Physical Journal A - Hadrons and Nuclei》2007,34(4):341-348
Direct mass measurements of nuclides near to the supposed end-point region of the astrophysical rp-process were performed
at SHIPTRAP, the Penning trap mass spectrometer at GSI Darmstadt. The masses of 24 nuclides were measured with relative uncertainties
between 5 . 10-8 and 2 . 10-7 . Three of them, 107Sb , 111I and 112I , were determined experimentally for the first time. The data analysis and mass evaluation are presented in detail. 相似文献
134.
S.?Djekic J.?Alonso H.-J.?Kluge W.?Quint S.?Stahl T.?Valenzuela J.?Verdú M.?VogelEmail author G.?Werth 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2004,31(3):451-457
The present work is concerned with the association of a temperature to a single ion stored in a Penning ion trap. Several methods are described which allow to determine the temperature by measurements of the ions cyclotron and axial trapping frequencies. Recent results of a measurement on a hydrogen-like carbon ion 12C5 + by use of mode coupling are presented and possible further applications are discussed.Received: 8 July 2004, Published online: 6 December 2004PACS:
07.20.-n. Thermal instruments and apparatus - 07.20.Dt. Thermometers - 42.50.Lc Quantum fluctuations - 42.50.Vk Mechanical effects of light on ions 相似文献
135.
Kellerbauer A. Blaum K. Bollen G. Herfurth F. Kluge H.-J. Kuckein M. Sauvan E. Scheidenberger C. Schweikhard L. 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,22(1):53-64
For a detailed study of the accuracy of the Penning trap mass spectrometer ISOLTRAP all expected sources of uncertainty were
investigated with respect to their contributions to the uncertainty of the final result. In the course of these investigations,
cross-reference measurements with singly charged carbon clusters 12C+
n were carried out. The carbon cluster ions were produced by use of laser-induced desorption, fragmentation, and ionization
of C60 fullerenes and injected into and stored in the Penning trap system. The comparison of the cyclotron frequencies of different
carbon clusters has provided detailed insight into the residual systematic uncertainty of ISOLTRAP and yielded a value of
8×10-9. This also represents the current limit of mass accuracy of the apparatus. Since the unified atomic mass unit is defined
as 1/12 of the mass of the 12C atom, it will be possible to carry out absolute mass measurements with ISOLTRAP in the future.
Received 7 June 2002 Published online 6 November 2002
RID="a"
ID="a"e-mail: a.kellerbauer@cern.ch
RID="b"
ID="b"Current address: Centre de Physique des Particules de Marseille, 13288 Marseille Cedex 9, France. 相似文献
136.
Y.K. Agarwal J. Recht H. Hübel M. Guttormsen D.J. Decman H. Kluge K.H. Maier J. Dudek W. Nazarewicz 《Nuclear Physics A》1983,399(1):199-210
Rotational properties of the 166Hf nucleus have been studied by in-beam spectroscopic methods using the 150Sm(20Ne, 4n)166Hf reaction. The ground band was observed up to the Iπ = 18+ level, the s-band from the Iπ = 12+ up to Iπ = 22+ level; in addition two side bands were found. The results are interpreted in terms of the pairing-self-consistent Hartree-Fock-Bogolyubov cranking model. Quantitative agreement between theory and experiment is obtained for the crossing of the ground band and s-band. The calculations predict a reduction of about 50 % in the neutron pairing energy gap of yrast states in the crossing region. The kinematical ((1)) and dynamical ((2)) moments of inertia are analysed. 相似文献
137.
138.
J. Fechner A. Hammesfahr A. Kluge S. K. Sen H. Toschinski J. Voss P. Weigt
B. Martin
《Nuclear Physics A》1969,130(3):545-562In a study of the level scheme of 131Cs, we have measured the γ-γ and the ce-γ directional correlations of the 496-123.7 keV and 486-133.5 keV cascades. The linear polarization at φ=90° was measured for the 496-123.7 keV and 486-133.5 keV cascades. The L-subshell ratios for the 123.7 keV transition were determined. The g-factor of the 133.5 keV level and the half-lives of the 78.7, 123.7, 133.5 and 216 keV levels were re-investigated. The spin and parity assignments derived for the 620, 133.5 and 123.7 keV levels are
, respectively. The 620, 496, 486, 133.5 and 123.7 keV transitions are found to be of pure E2, pure M1, pure E2, (M1+(22±2)%E2) and pure E2 multipolarity, respectively. An upper limit of 192 ps for the half-life of the 216 keV level is obtained. The results are compared with theoretical estimates from the calculations of Kisslinger and Sorensen, of Freed and of Freed and Miles. 相似文献
139.
C. Duke H. Fischer H.-J. Kluge H. Kremmling Th. Kühl E.-W. Otten 《Physics letters. A》1977,60(4):303-306
By use of a pulsed tunable dye laser the isotope shift of 190Hg in the , λ = 2537 Å line has been measured at the on-line mass separator ISOLDE/CERN. The preliminary result relative to 204Hg is . 相似文献
140.