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31.
J. Domscheit S. Trmnen B. Aengenvoort H. Hübel R. A. Bark M. Bergstrm A. Bracco R. Chapman D. M. Cullen C. Fahlander S. Frattini A. Grgen G. B. Hagemann A. Harsmann B. Herskind H. J. Jensen S. L. King S. Lenzi D. Napoli S. W.
degrd C. M. Petrache H. Ryde U. J. van Severen G. Sletten P. O. Tjm C. Ur 《Nuclear Physics A》1999,660(4):1211-392
High-spin states in 163Lu have been investigated using the Euroball spectrometer array. The previously known superdeformed band has been extended at low and high energies, and its connection to the normal-deformed states has been established. From its decay the mixing amplitude and interaction strength between superdeformed and normal states are derived. In addition, a new band with a similar dynamic moment of inertia has been found. The experimental results are compared to cranking calculations which suggest that the superdeformed bands in this mass region correspond to shapes with a pronounced triaxiality (γ≈±20°). 相似文献
32.
Crystals of ordered Ba6EuF12Cl2 were found to form during high temperature flux growth. The structure was refined in the hexagonal space group P 6 to RF(R ) = 0.024(0.024) for 326 reflections and 46 parameters. Lattice parameters are a = b = 1059.27(8) pm and c = 416.36(2) pm; Z = 1. The structure is isotypic to Ba7F12Cl2. No solid solution of Ba/Eu was observed, the Eu2+ ions are located in the channels formed by 3 + 6 fluorine ions, occupying only one of the three metal sites of the Ba7F12Cl2 structure. 相似文献
33.
W. Bartel L. Becker D. Cords R. Felst K. Hagiwara D. Haidt H. Junge G. Knies H. Krehbiel P. Laurikainen R. Meinke B. Naroska J. Olsson D. Schmidt P. Steffen G. Dietrich J. Hagemann S. Yamada 《Physics letters. [Part B]》1985,155(4):288-294
A search was performed for the associated production of two different Higgs bosons via a virtual Z0 in e+e? annihilation (e+e? → h10h20) using the JADE detector at PETRA. This was motivated by the interpretation of the monojet events observed at the CERN p collider as anomalous Z0 decays into two neutral Higgs bosons (h10 and h20), where h10 is stable and escapes detection while h20 decays into hadrons. Single- or di-jet events with large momentum imbalance are then expected at PETRA energies. No evidence for such events was found in our data; this excludes h20 masses in the range of 1 to 21 GeV with 95% CL, if the branching fraction for Z0 → h10h20 is a larger than one half that for . The possibility that the monojets could originate from supersymmetric higgsino production from Z0 decay is also examined. 相似文献
34.
G.B. Hagemann J.D. Garrett B. Herskind J. Kownacki B.M. Nyakó P.L. Nolan J.F. Sharpey-Schafer P.O. Tjøm 《Nuclear Physics A》1984,424(2):365-382
155Ho and 157Ho have been populated in the reactions 141Pr(18O,4n) and 146Nd(15N, 4n) at 85 and 74 MeV, respectively. In both nuclei bands built on the ?[523] configuration were established to spin values considerably above the first backbend. A signature dependence in the excitation energies as well as in the ratio of M1 to E2 transition rates is observed below, but not above, the backbend in both nuclei. In 157Ho lifetimes were measured with the recoil-distance method. The ΔI = 2; E2 transition probabilities obtained show very little variation with either signature or spin and no irregularity at the backbend. The signature dependence and strong rise in the ratio B(M1)/B(E2) observed at the backbend in 157Ho therefore must be caused by the B(M1) values. A signature dependence in the B(E2, I → I ?1)/B(E2, I → I ?2) ratios also found in 157Ho below the backbend is mainly the result of signature dependence in the ΔI = 1 ; E2 transition rates. Qualitatively, most of the features observed can be explained by nonaxial deformations, which change from large negative to slightly positive values of γ at the backbend. 相似文献
35.
36.
W. Bartel L. Becker D. Cords R. Felst D. Haidt H. Junge G. Knies H. Krehbiel P. Laurikainen K. Meier R. Meinke B. Naroska J. Olsson D. Schmidt P. Steffen G. Dietrich J. Hagemann S. Yamada 《Physics letters. [Part B]》1985,157(4):340-344
Distributions of particles in three-jet events from e+e? → hadrons are compared with different fragmentation schemes, i.e. the Lund string model, independent parton fragmentation and QCD shower models. Effects specific to the string scheme, which have been seen in the data, are also reproduced by QCD shower models if soft gluon interference effects are included. 相似文献
37.
H. J. Jensen R. A. Bark R. Bengtsson G. B. Hagemann P. O. Tjøm S. Y. Araddad C. W. Beausang R. Chapman J. Copnell A. Fitzpatrick S. J. Freeman S. Leoni J. C. Lisle J. Simpson A. G. Smith D. M. Thompson S. J. Warburton J. Wrzesiński 《Zeitschrift für Physik A Hadrons and Nuclei》1997,359(2):127-132
Theπh9/2[541 1/2?] band in 167Tm has been studied through the 124Sn(48Ca, p4n)167Tm reaction at E beam = 210 MeV. The favoured signature of the πh9/2[541 1/2?] band is observed to spin 61/2h?. A remarkable small gain in aligned angular momentum at the AB-band crossing has been found. The crossing frequency and the gain in aligned angular momentum for 167Tm are compared with data for the N = 98 isotones of Lu, Ta and Re, and contrasted with Cranked Shell Model predictions, based on frequency diabatic configurations. Large deviations are found for the gain in aligned angular momentum. 相似文献
38.
M. Loewe J. de Boer H. J. Maier M. Würkner P. Olbratowski J. Srebrny J. Choinski T. Czosnyka J. Iwanicki P. J. Napiorkowski G. Hagemann G. Sletten S. A. Karamian P. von Neumann-Cosel A. Richter C. Schlegel H. J. Wollersheim 《Zeitschrift für Physik A Hadrons and Nuclei》1996,354(1):9-10
The new radon isotope197Rn was produced in the reaction169Tm(35Cl, 7n)197Rn using bombarding energies from 5.6 to 6.1 MeV/nucleon. Fusion products were separated in-flight from the primary beam using a gas-filled recoil separator. The alpha particle energy and half-life of197Rn were measured to be (7260±7) keV and (65 ?14 +25 ) ms, respectively. Another new alpha line was assigned to an isomeric state in197Rn for which an alpha particle energy of (7356±7) keV and a half-life of (19 ?4 +8 ) ms were obtained. 相似文献
39.
Hermann Hagemann 《Angewandte Chemie (International ed. in English)》1977,16(11):743-750
Cl? CO? N?C?O (N-chlorocarbonyl isocyanate) is prepared in 90% yield by partial hydrolysis of the addition product of phosgene and cyanogen chloride. Many derivatives of the iminocarboxylic acid parent compound can be obtained from this highly reactive species. Both the acid chloride and the isocyanate group are amenable to reactions exhibiting overall selctivity, and this opens the way, inter alia, to a simple preparative synthesis of isocyanates from alcohols, phenols, thiols, and thiophenols. Combination of the two functional groups and their peculiar symmetry, which becomes evident, e.g. in the HCl adduct, facilitates ready cyclization of N-chlorocarbonyl isocyanate under very mild conditons. 相似文献
40.
Crystals of the chemical composition Ba7F12Cl2 were modified by adding a small amount of Ca2+ to allow the synthesis of the corresponding bromine compound Ba[Ca]7F12Br2. These samples were prepared in a NaBr flux and characterized by single crystal x‐ray diffraction. The new structure crystallizes in a disordered arrangement in the hexagonal space group P63/m (176). The calcium ion has a coordination number of 6. Solid solutions on the heavy halide position can be synthesised in a NaCl/NaBr flux to obtain the compounds Ba7?xCaxF12(ClyBr1?y)2 with x = ~0.5 and 0 < y < 1. Regardless the amount of calcium used in the preparation process, the Ca stoichiometry in the compound is always between 0.3 and 0.5. The lattice parameters differ depending on the Ca‐ and Br‐content between 1053.81(5) ? a = b ? 1058.93(3) pm and 421.21 ? c ? 426.78(3) pm. 相似文献