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101.
102.
D.J. Morrissey G.J. Wozniak L.G. Sobotka A.J. Pacheco R.J. McDonald C.C. Hsu L.G. Moretto 《Nuclear Physics A》1982,389(1):120-140
The average magnitude and alignment of the intrinsic spin of the heavy partner from the reaction of 252 MeV 20Ne with 197Au and 238U were determined as a function of Q-value. These spin values were extracted from sequential fission angular distributions obtained in coincidence with projectile-like products. For all Q-values a large out-of-plane anisotropy was observed, while for large negative Q-values an in-plane anisotropy was observed. A very large entrance-channel mass-asymmetry was chosen to provide a stringent test of equilibrium statistical model predictions for the spin alignment. The importance of determining the direction of the line-of-centers of the dinuclear system at scission is discussed. Large values of PZZ were deduced for all Q- values. PXY was observed to be positive in the quasielastic region and negative in the deep-inelastic region. The extracted alignment data are compared to equilibrium statistical model calculations. 相似文献
103.
104.
The lowest four levels of 17O have been observed as resonances in the 13C(α, n)16O reaction. Excitation energies and widths obtained for these levels are 11.076 ± 0.005 MeV, Γc.m. = 5.0 ± 1.1 keV; 12.458 ± 0.005 MeV, Γc.m. = 8 ± 2 keV; 12.944 ± 0.006 MeV, Γc.m. = 6 ± 2 keV; 12.993 ± 0.006 MeV, Γc.m. < 3 keV. The total and partial decay widths for the lowest level are much larger than those of the analogue level in 17F, implying significant isotensor components in the admixtures. 相似文献
105.
106.
A study of neutron time-of-flight spectra from the 4He(3He, n)6 reaction at E3He = 38.61 MeV, sets a one standard deviation upper limit of 7 μb/sr for the cross section to a possible narrow level near the 3He + 3He threshold. 相似文献
107.
Morton Kaplan David J. Moses Dag Ø. Eriksen Mehmet Kildir Douglas R. G. Logan Michael S. Zisman Richard J. McDonald 《Zeitschrift für Physik A Hadrons and Nuclei》1983,313(1-2):31-37
Inclusive4He and4H energy spectra and heavy fragment coincidence correlations have been measured for reactions of 7.31 MeV/u238U with238U and?197Au targets. The H/He production cross sections are in the range 15–26 mb, and their emission spectra are very similar for the two systems. The observed strong kinematic shifts with angle are reproduced in shape and magnitude by Monte Carlo simulations of particle evaporation from projectile-like and target-like fragments, indicating competition between charged particle emission and sequential fission. No evidence is found for high energy charged particle emission associated with ultra-highZ composite systems. Heavy fragment measurements indicate an abundance of quasielastic and deeply inelastic reaction fragments, as well as sequential fission of target and projectile nuclei. For238U nuclei, the fission occurs predominantly in an asymmetric mode, reminiscent of fission at low excitation energy. For238+238U reactions in the vicinity of the grazing angle, the frequency of single sequential fission (with survival of the partner fragment) is twice as large as double sequential fission in which both the target and projectile undergo fission. In238U+197Au reactions, the survival probability of the heavy fragments is even greater. The surprisingly high survival probabilities of high-Z fragments imply a preponderance of very soft collisions in these very-heavy-ion reactions, at least at energies not very far over the Coulomb barrier. 相似文献
108.
J.A. Kuehner J. Szücs P. Ikossi A.M. McDonald D.T. Petty 《Physics letters. [Part B]》1977,66(1):32-34
A new technique for gamma-ray angular correlation measurements using tensor polarized deuterons is illustrated with the reaction. The 4.77 MeV level of 22Na is assigned Jπ = 3+ and the transition to the 1.95 MeV level is determined to be pure magnetic dipole. 相似文献
109.
A technique involving the use of an inflatable rubber bag to apply a uniform load to a single open-web steel joist, which could also be used in the testing for any similar two-dimensional structural member, is described and compared to the method of applying a dead load of known weight. The advantages of this technique over concentrated-load testing and the dead-load method are briefly discussed. 相似文献
110.
Rankin MA McDonald R Ferguson MJ Stradiotto M 《Angewandte Chemie (International ed. in English)》2005,44(23):3603-3606