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Stephen P. Birkeland Guido H. Daub F. Newton Hayes Donald G. Ott 《Zeitschrift für Physik A Hadrons and Nuclei》1960,159(5):516-523
A number of new 2- and 2,7-aryl substituted phenanthrenes, 3,4-dihydrophenanthrenes, and 9,10-dihydrophenanthrenes, as well as some relatedp-quaterphenyls andp-terphenyls, were tested as liquid scintillation solutes. Also determined were the compounds' ultraviolet absorption spectra, ultraviolet-induced fluorescence spectra, and Kallmann parameters. On the basis of these measurements, it was possible to correlate to some degree structure and scintillation ability. Some interesting results regarding conjugation and co-planarity in the linear polyphenyls were also obtained. 相似文献
54.
David E. Newton 《School science and mathematics》1971,71(6):531-534
55.
The overcompleteness of the basis states when Anderson's Hamiltonian is applied to chemisorption is allowed for by using a pseudopotential to describe the atom-metal coupling. Some calculations for hydrogen on free-electron Al are reported. 相似文献
56.
It is shown that associated with any sufficiently sharp resonance there is a delayed emergence of particles that under suitable conditions follows an exponential law of decay to an excellent approximation over many lifetimes. The dependence of the duration of the exponential curve on the resonance width, on the excitation width, and on the observation distance, is examined in detail. 相似文献
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D. Ward G.D. Dracoulis J.R. Leigh R.J. Charity D.J. Hinde J.O. Newton 《Nuclear Physics A》1983,406(3):591-612
Levels to spin 16+ in the ground band and 17? in the octupole band in 222Th have been identified using the reaction 208Pb(18O, 4n)222Th at 93 MeV. To suppress intense γ-ray background from fission a residue detector was built and operated in coincidence with the Ge(Li) and NaI(Tl) detectors. The apparent moment of inertia in the ground-state rotational band rises very rapidly with increasing spin, however, no indications of backbending were observed. The octupole band at low spin has an aligned angular momentum relative to the ground-state band. Strong cross-band E1 transitions competed with collective E2 transitions within each band. Analysis showed that the ratios were within experimental uncertainty independent of both the spin and parity of the parent state.The average γ-ray multiplicity per cascade was measured for 222Th. The results were in reasonable agreement with the computer code ORNL-ALICE. 相似文献
60.
D. P. Barber J. B. Dainton L. C. Y. Lee R. Marshall J. C. Thompson D. T. Williams T. J. Brodbeck G. Frost G. N. Patrick G. F. Pearce D. Newton T. Sloan G. R. Brookes W. J. Haynes P. B. Wilkes LAMP Group 《Zeitschrift fur Physik C Particles and Fields》1984,26(3):343-351
The differential and total corss sections and the decay density matrix elements have been measured for the reactions, γp→ωp and γp→ωΔ+ (1232) in the photon energy range 2.8 to 4.8 GeV. The total cross sections for ωΔ+ (1232) photo-production are found to be slightly larger than those for elastic ω photo-production in this energy range. The data are compared to the predictions of a theoretical model and the contributing exchange mechanics are discussed. 相似文献