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11.
The233Th(3He,d)233Pa and233Th(α, t)233Pa reactions were studied with 28.5-MeV3He and 30-MeV α-particles, respectively. The reaction results are interpreted in terms of a distorted-wave Born-approximation analysis. Transferred angular momenta are deduced from (α, t) and (3He,d) cross-section ratios,R=dσ(α, t)/dσ(3He,d). Theoretical cross sections, calculated in the framework of the Nilsson model with pairing and Coriolis interactions included, are in reasonable agreement with experiment. Rotational bands built on the following Nilsson proton configurations are identified in233Pa: 1/2?[530↑], 3/2+[651↑], 1/2+[660↑], 5/2+[642↑], 5/2?[5231↓], and 3/2?[521↑]. 相似文献
12.
H. -Th. Elze U. Heinz K. Kajantie T. Toimela 《Zeitschrift fur Physik C Particles and Fields》1988,37(2):305-313
The polarisation tensor of gluons in high temperature QCD matter is discussed in the back-ground gauge and compared with that in the temporal axialA 0=0 gauge. In both of these the gluon polarisation tensor alone is sufficient to give the asymptotically free sign of the QCD beta function. In the former the beta function and the imaginary part of the polarisation tensor are coupled in such a way that asymptotic freedom implies instability of plasma oscillations. In the latter, due to the non-covariance of the gauge condition, the beta function and the imaginary part are decoupled in such a way that the sign of the imaginary part corresponds to stable plasma oscillations. 相似文献
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14.
H. J. Wollersheim P. Egelhof H. Emling J. Gerl W. Henning R. Holzmann R. Schmidt R. S. Simon N. Martin G. Eckert Th. W. Elze K. Stelzer R. Kulessa G. Duchene B. Haas J. C. Merdinger J. P. Vivien J. de Boer E. Hauber K. Kaiser P. von Brentano R. Reinhardt R. Wirowski R. Julin C. Fahlander I. Thorslund H. Kluge 《Zeitschrift für Physik A Hadrons and Nuclei》1992,341(2):137-144
Collective properties of206,208Pb have been investigated with gamma-ray spectroscopy using nuclear and electromagnetic excitation by208Pb projectiles. From the measurement of particle-particle- and particle-particle- coincidences a new energy level in208Pb at 5.683 MeV was observed and the data suggest an interpretation as a 2-phonon octupole vibrational state with spin 4+ or 6+. For this state one finds the same dynamical deformation parameter
3 as for the first-excited collective 3– state. The results are compared to predictions of models which consider, in particular, the aspects of the quadrupole interaction and the interaction of the 2-particle pairing vibration with the 2-phonon octupole vibration. For the206Pb+208Pb system at 6.2 MeV/u the nuclear potential could be determined from the measured inelastic cross sections.Dedicated to Prof. Dr. P. Kienle on the occasion of his 60th birthday 相似文献
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Zinser M Humbert F Nilsson T Schwab W Blaich T Borge MJ Chulkov LV Eickhoff H Elze TW Emling H Franzke B Freiesleben H Geissel H Grimm K Guillemaud-Mueller D Hansen PG Holzmann R Irnich H Jonson B Keller JG Klepper O Klingler H Kratz JV Kulessa R Lambrecht D Leifels Y Magel A Mohar M Mueller AC Münzenberg G Nickel F Nyman G Richter A Riisager K Scheidenberger C Schrieder G Sherrill BM Simon H Stelzer K Stroth J Tengblad O Trautmann W Wajda E Zude E 《Physical review letters》1995,75(9):1719-1722
16.
We review Smoothed Particle Hydrodynamics (SPH) for ultrarelativistic nuclear collisions. Possible extensions of the usual formulation are discussed, incorporating the fundamentally important single-event fluctuations originating in turbulent or quantum mechanical motion. 相似文献
17.
D. Lambrecht T. Blaich T. W. Elze H. Emling H. Freiesleben K. Grimm W. Henning R. Holzmann J. G. Keller H. Klingler J. V. Kratz R. Kulessa S. Lange Y. Leifels E. Lubkiewicz E. F. Moore W. Prokopowicz R. Schmidt C. Schütter H. Spies K. Stelzer J. Stroth E. Wajda W. Waluś M. Zinser E. Zude 《Zeitschrift für Physik A Hadrons and Nuclei》1994,350(2):115-120
We investigate the beam energy dependence of neutron and proton squeeze-out in collisions of197Au+197Au atE/A=400—800 MeV. The azimuthal anisotropy that describes the enhanced emission of mid-rapidity neutrons perpendicular to the reaction plane rises strongly with the transverse momentum of the neutrons. This dependence of the azimuthal anisotropy follows a universal curve — independent of beam energy — if the neutron momenta are measured in fractions of the projectile momentum per mass unit. Analogously, the kinetic energy spectra of mid-rapidity neutrons exhibit a universal behaviour as a function of the kinetic energy of the projectile.
The members of the FOPI-collaboration: J.P. Alard, Z. Basrak, N. Bastid, I.M. Belayev, M. Bini, R. Bock, A. Buta, R. aplar, C. Cerruti, N. Cindro, J.P. Coffin, M. Crouau, P. Dupieux, J. Erö, Z.G. Fan, P. Fintz, Z. Fodor, R. Freifelder, L. Fraysse, S. Frolov, A. Gobbi, Y. Grigorian, G. Guillaume, N. Herrmann, K.D. Hildenbrand, S. Hölbling, O. Houari, S.C. Jeong, M. Jorio, F. Jundt, J. Kecskemeti, P. Koncz, Y. Korchagin, R. Kotte, M. Krämer, C. Kuhn, I. Legrand, A. Lebedev, C. Maguire, V. Manko, T. Matulewicz, G. Mgebrishvili, J. Mösner, D. Moisa, G. Montarou, P. Morel, W. Neubert, A. Olmi, G. Pasquali, D. Pelte, M. Petrovici, G. Poggi, F. Rami, W. Reisdorf, A. Sadchikov, D. Schüll, Z. Seres, B. Sikora, V. Simion, S. Smolyankin, U. Sodan, N. Taccetti, K. Teh, R. Tezkratt, M. Trzaska, M.A. Vasiliev, P. Wagner, J.P. Wessels, T. Wienold, Z. Wilhelmi, D. Wohlfarth, A.V. Zhilin. 相似文献
18.
S. Wan J. Gerl J. Cub J.M. Holeczek P. Reiter D. Schwalm T. Aumann K. Boretzky W. Dostal B. Eberlein H. Emling Ch. Ender Th.W. Elze H. Geissel A. Grünschloß R. Holzmann N. Iwasa M. Kaspar A. Kleinböhl O. Koschorrek Y. Leifels A. Leistenschneider I. Peter H. Schaffner C. Scheidenberger R. Schubart R. Schubert H. Simon G. Stengel A. Surowiec H.J. Wollersheim 《The European Physical Journal A - Hadrons and Nuclei》1999,6(2):167-174
This work demonstrates the feasibility of in-beam %-spectroscopy employing radioactive ion beam species at relativistic energies of E = 210 ~ 280 A · MeV. Neutron-rich nuclei below 48Ca with neutron number between the two magic numbers 20 and 28 have been investigated. Using a Pb target, single step inelastic excitation originating mainly from Coulomb interaction takes place populating preferentially low-lying low-spin states and enabling the extraction of B(E2) values. On a C target, nucleon removal reactions are dominating and medium-spin states are populated thus offering spectroscopic information in neighboring nuclei. Cross sections of inelastic excitation are determined and compared to coupled-channels calculations. Two new states of the very neutron-rich nucleus 44Ar at 1.78(8) MeV and 2.61(16) MeV are deduced from %-transitions. 相似文献
19.
H. Ower Th.W. Elze J. Idzko K. Stelzer E. Grosse H. Emling P. Fuchs D. Schwalm H.J. Wollersheim N. Kaffrell N. Trautmann 《Nuclear Physics A》1982,388(2):421-444
Multiple Coulomb excitation of 232Th, 234U and 236U by 5.3 208Pb ions has been studied using γ-ray spectroscopy. Excitation of ground-band levels is observed up to spin Iπ = 26+ (tentatively 28 +) in 232Th and 234U and Iπ = 28+ (tentatively 30+)in 236U. High-spin levels of the Kπ = 0? octupole-vibrational bands are also observed in these nuclei. The measured transition energies between ground-band levels suggest that at several units of angular momentum are carried by single particles aligned with the rotation axis.This result can be understood in terms of a super band built on aligned two-quasiparticle configurations which crosses the ground-state rotational band at a rotational frequency of . The E2 transition-matrix elements deduced from the experimental γ-yields agree within their errors with the rigid-rotor predictions up to the highest spins observed.The experimental results are discussed using the concept of rotation alignment and are compared with predictions of the rotation-vibration model and the interacting-boson model. 相似文献
20.
Meister M Markenroth K Aleksandrov D Aumann T Axelsson L Baumann T Borge MJ Chulkov LV Dostal W Eberlein B Elze TW Emling H Forssén C Geissel H Hellström M Holzmann R Jonson B Kratz JV Kulessa R Leifels Y Leistenschneider A Mukha I Münzenberg G Nickel F Nilsson T Nyman G Richter A Riisager K Scheidenberger C Schrieder G Simon H Tengblad O Zhukov MV 《Physical review letters》2002,88(10):102501
Low-lying resonance states in 7He(6He+n), formed after fragmentation reactions of a 227 MeV/nucleon 8He beam on a carbon target, have been studied. Coincidences between 6He nuclei and neutrons, corresponding to the one-neutron knockout channel in 8He, were selected. The relative energy spectrum in the 6He+n system shows a structure, which is interpreted as the 7He ( Ipi = 3/2(-)) ground state, unbound with 0.43(2) MeV relative to the 6He+n system and a width of Gamma = 0.15(8) MeV overlapping with an excited ( Ipi = 1/2(-)) state observed at 1.0(1) MeV with a width of Gamma = 0.75(8) MeV. 相似文献