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41.
Mukherjee M Kellerbauer A Beck D Blaum K Bollen G Carrel F Delahaye P Dilling J George S Guénaut C Herfurth F Herlert A Kluge HJ Köster U Lunney D Schwarz S Schweikhard L Yazidjian C 《Physical review letters》2004,93(15):150801
Mass measurements with a relative precision of better than 1.5 x 10(-8) were performed on 22Mg and its reaction partners 21Na and 22Na with the ISOLTRAP Penning trap mass spectrometer at CERN, yielding the mass excesses D(22Mg)=-399.92(27) keV, D(21Na)=-2184.71(21) keV, and D(22Na)=-5181.56(16) keV. The importance of these results is twofold. First, a comparative half-life (Ft value) has been obtained for the superallowed beta decay of 22Mg to further test the conserved-vector-current hypothesis. Second, the resonance energy for the 21Na proton capture reaction has been independently determined, allowing direct comparisons of observable gamma radiation in nova explosions with the yield expected from models. 相似文献
42.
Hermanspahn N Haffner H Kluge H Quint W Stahl S Verdu J Werth G 《Physical review letters》2000,84(3):427-430
We report on the first observation of the continuous Stern-Gerlach effect on an electron bound in an atomic ion. The measurement was performed on a single hydrogenlike ion ( 12C5+) in a Penning trap. The measured g factor of the bound electron, g = 2.001 042(2), is in excellent agreement with the theoretical value, confirming the relativistic correction at a level of 0.1%. This proves the possibility of g-factor determinations on atomic ions to high precision by using the continuous Stern-Gerlach effect. The result demonstrates the feasibility of conducting experiments on single heavy highly charged ions to test quantum electrodynamics in the strong electric field of the nucleus. 相似文献
43.
G. Bollen F. Ames G. Audi D. Beck J. Dilling O. Engels S. Henry F. Herfurth A. Kellerbauer H.-J. Kluge A. Kohl E. Lamour D. Lunney R. B. Moore M. Oinonen C. Scheidenberger S. Schwarz G. Sikler J. Szerypo C. Weber 《Hyperfine Interactions》2001,132(1-4):213-220
Penning trap mass spectrometry has reached a state that allows its application to very short-lived nuclides available from
various sources of radioactive beams. Mass values with outstanding accuracy are achieved even far from stability. This paper
illustrates the state of the art by summarizing the status of the ISOLTRAP experiment at ISOLDE/CERN. Furthermore, results
of mass measurements on unstable rare earth isotopes will be given.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
44.
Samit Mandal J Gerl H Geissel K Hauschild M Hellström Z Janas I Kojouharov Y Kopatch RC Lemmon P Mayet Z Podolyak PH Regan H Schaffner C Schlegel J Simpson HJ Wollersheim 《Pramana》2001,57(1):161-164
Feasibility of gamma-ray spectroscopy at relativistic energies with exotic heavy-ions and new generation of germanium detectors
(segmented Clover) is discussed. An experiment with such detector array and radioactive is discussed. 相似文献
45.
46.
47.
Yu. A. Litvinov F. Attallah K. Beckert F. Bosch M. Falch B. Franzke H. Geissel M. Hausmann Th. Kerscher O. Klepper H.-J. Kluge C. Kozhuharov K. E. G. Löbner G. Münzenberg F. Nolden Yu. N. Novikov Z. Patyk W. Quint T. Radon C. Scheidenberger M. Steck L. Vermeeren H. Wollnik 《Hyperfine Interactions》2001,132(1-4):281-287
Projectile fragments of a 209Bi beam were separated in flight with the fragment separator FRS and injected into the experimental storage ring ESR. In the
ESR a beam containing up to about 100 different isotopes was cooled to a relative velocity spread of δv/v=10−6 by means of the electron cooler. The image currents of the ions induced in a Schottky pick-up probe at each turn were recorded.
A subsequent Fast Fourier Transformation of these signals yields the revolution frequencies of the different isotopes stored
in the ESR. Unknown masses of more than 150 neutron-deficient nuclides in the element range of 52≤Z≤85 have been measured directly by Schottky Mass Spectrometry and in addition more than 60 new masses have been obtained from
α-decay chains. These new mass data allow the location of the one-proton dripline and the prediction of the two-proton dripline
for heavy nuclides. The experimental masses are compared with different theoretical predictions.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
48.
49.
G. Ulm S. K. Bhattacherjee P. Dabkiewicz G. Huber H. -J. Kluge T. Kühl H. Lochmann E. -W. Otten K. Wendt S. A. Ahmad W. Klempt R. Neugart ISOLDE Collaboration 《Zeitschrift für Physik A Hadrons and Nuclei》1986,325(3):247-259
The technique of collinear fast-beam laser spectroscopy has been used to measure the isotope shifts of the even-even isotopes of Hg (Z=80) in the mass range 182≤A≤198 at the on-line mass separator ISOLDE at CERN. The atomic transition studied (6s 6p 3 P 2- 6s7s 3 S 1,λ=546.1 nm) starts from a metastable state, which is populated in a quasi resonant charge transfer process. The resulting changes in nuclear mean square charge radii show clearly that182Hg follows the trend of the heavier, even, weakly oblate isotopes. Correspondingly the huge odd-even shape staggering in the light Hg isotopes continues and the nuclear shape staggering and shape coexistence persists down to the last isotope investigated,181Hg. An update of isotope shift and hyperfine structure data for181–206Hg is given, with a revised evaluation of the differences in nuclear mean square charge radii and of spectroscopic quadrupole moments. 相似文献
50.
F. Ames T. Brumm K. Jäger H. -J. Kluge B. M. Suri H. Rimke N. Trautmann R. Kirchner 《Applied physics. B, Lasers and optics》1990,51(3):200-206
We report here on the development of a high-temperature laser ion source useful for trace analysis and other applications. It consists of a high temperature ionization chamber, three tunable dye lasers pumped by copper vapor lasers for stepwise resonant ionization and a Mattauch-Herzog mass spectrometer for the analysis of photo-ions. The principle of the laser ion source and its theoretical efficiency are discussed, where the efficiency of a laser ion source is the ratio of photo-ions extracted out to the number of atoms introduced into the cavity. Experimentally, an efficiency of 2×10–3 has been achieved for technetium. The scheme of gated detection is described which is used for suppressing isobaric background of molybdenum. The possible improvements are briefly mentioned for achieving isotopic analysis of 108 atoms of 97,98Tc in the presence of 1015 atoms of molybdenum, as separated chemically from molybdenum ore. Such an analysis of technetium isotopes produced in molybdenite ore by a (v,e
–) reaction, is expected to yield information about the solar neutrino flux.Permanent address: Bhabha Atomic Research Centre, Bombay 400085, India 相似文献