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101.
F. Strieder L. Gialanella U. Greife C. Rolfs S. Schmidt W. H. Schulte H. P. Trautvetter D. Zahnow F. Terrasi L. Campajola A. D’Onofrio V. Roca M. Romano M. Romoli 《Zeitschrift für Physik A Hadrons and Nuclei》1996,355(1):209-218
The absolute cross sectionσ of thed(7Li,p)8Li reaction near theE cm=0.61 MeV resonance has been measured using a7Li ion beam and a windowless gas target system filled with D2 gas. The proton yield of the reaction and theβ-delayedα-activity of the residual nuclides8Li were observed both concurrently with the elastic scattering yield, relatingσ to the Rutherford scattering cross sectionσ R. The resulting values,σ (fromp)=143.6±8.9 mb andσ (from8Li)=151±20 mb, lead to a weighted mean value ofσ=153±6 mb (x 2=2.26) including all available values andσ=146±5 mb (x 2=0.05) removing some values from the data set. The consequences for the expected flux of high-energy solar neutrinos are discussed. 相似文献
102.
A Ge(Li) spectrometer was used to measure the temperature-dependence of the intensity of gamma rays resulting from positron annihilation in single crystals of Pb, Sn, Ge and Cu. In contrast to recent angular distribution results, no significant temperature effects were observed. 相似文献
103.
H. Gr?ssler D. Lanske R. Schulte G.T. Jones R.P. Middleton S.W. ONeale K. B?ckmann W. Gebel C. Geich-Gimbel B. Nellen A. Grant H. Klein D.R.O. Morrison P. Schmid H. Wachsmuth J.S. Chima M.M. Mobayyen J. Wells 《Nuclear Physics B》1983,223(2):269-295
In an experiment with the hydrogen bubble chamber BEBC at CERN multiplicities of hadrons produced in νp and interactions have been investigated. Results are presented on the multiplicities of charged hadrons and neutral pions, forward and backward multiplicities of charged hadrons and correlations between forward and backward multiplicities. Comparisons are made with hadronic reactions and e+e? annihilation. In the framework of the quark-parton model the data imply similar charged multiplicities for the fragments of a u- and a d-quark, and a larger multiplicities for the fragments of a uu- than for a ud-diquark. The correlation data suggest independent fragmentation of the quark and diquark for hadronic masses above ~ 7 GeV and local charge compensation within an event. 相似文献
104.
105.
P. C. Lichtenberger C. W. Schulte I. K. MacKenzie 《Applied Physics A: Materials Science & Processing》1975,6(3):305-307
The equilibrium lineshape for positrons annihilating in Cd shows an anomalous temperature dependence which complicates analysis for vacancy formation energies. The phenomenon, tentatively identified as trapping by transient dilatations, probably occurs in all metals. 相似文献
106.
Ferreira da Silva P Lima JC Freitas AA Shimizu K Maçanita AL Quina FH 《The journal of physical chemistry. A》2005,109(32):7329-7338
Color intensification of anthocyanin solutions in the presence of natural polyphenols (copigmentation) is re-interpreted in terms of charge transfer from the copigment to the anthocyanin. Flavylium cations are shown to be excellent electron acceptors (E(red) approximately -0.3 V vs SCE). It is also demonstrated, for a large series of anthocyanin-copigment pairs, that the standard Gibbs free energy of complex formation decreases linearly with EA(Anthoc) - IP(Cop), the difference between the electron affinity of the anthocyanin, EA(Anthoc), and the ionization potential of the copigment, IP(Cop). Based on this correlation, copigmentation strengths of potential candidates for copigments can be predicted. 相似文献
107.
G. Berg W. Kühn H.Paetz gen. Schieck K. Schulte P. von Brentano 《Nuclear Physics A》1975,254(1):169-182
The low cross sections in the diffraction minima of elastic proton scattering at 12.5 MeV incident energy and far backward scattering angles for target nuclei with mass numbers A of about 90 were used to investigate compound nucleus effects in the framework of the statistical model. In the case of 90Zr(p, p′) energy averaged T< fluctuations are observed, while in the case of 88Sr(p, p0) resolved structures with a coherence width of Γ = 22 keV are found, which is assumed to be the coherence width Γ> of overlapping T> states. 相似文献
108.
F.K. Schulte 《Surface science》1976,55(2):427-444
Electron densities, potentials, and work functions of thin metal films are calculated self-consistently. The planar uniform-background model and the density-functional formalism are used similarly as in the theory of metal surfaces by Lang and Kohn. Electron densities and potentials are discussed for rs = 4 both as function of the position in the film and of film thickness. Numerical results for the dependence of the work function on film thickness are given for rs = 2, 3, 4, 5, 6. As functions of film thickness electron densities, potentials and work functions show oscillations with a period of one-half the Fermi wavelength. The amplitude of the oscillations in potentials and work functions is about 1 eV for one monolayer and 0.1 eV for films of 20 Å thickness. A comparison with non-self-consistent calculations reveals the necessity of self-consistent computations. The relevance of the results to work function measurements and to investigations of thermodynamic and transport properties are discussed. The influence of the film geometry on calculations designed for surfaces per se is examined. 相似文献
109.
F. K. Schulte 《Zeitschrift für Physik B Condensed Matter》1977,27(4):303-307
Starting from a definition of the work function in terms of total energies of the electron system it is shown that this work function can be obtained from the single-particle Schrödinger equations in the density-functional formalism in the way suggested by the Sommerfeld model. It is also shown that the change of the equilibrium ion positions accompanying the ionization of the crystal has no influence on the work function. A comparison is made with Koopmans' theorem. The use of several potentials for computations of the work function is critically investigated. 相似文献
110.
Errors caused by instrumental instabilities in annihilation photon energy spectrometers can be much larger than statistical
errors. The performance of a typical spectrometer is investigated in detail and both empirical and theoretical approaches
to correcting data for residual fluctuations are examined. 相似文献