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V. V. Ammosov E. N. Ardashev D. S. Baranov V. I. Hleborad A. A. Ivanilov P. V. Ivanov V. I. Konyushko V. M. Korablev V. A. Korotkov V. V. Makeev A. G. Myagkov N. A. Netyaga A. Yu. Polyarush A. A. Sokolov E. P. Kuznetsov H. -J. Grabosch H. H. Kaufmann U. Krecker R. Nahnhauer S. Nowak S. Schlenstedt H. Vogt SKAT-Collaboration 《Zeitschrift fur Physik C Particles and Fields》1986,30(2):183-189
For charged current neutrino nucleus interactions at energies below 30 GeV, resulting from an experiment with the freon filled bubble chamber SKAT,K 0 and Λ production is investigated. An estimation of the total strange and charm production cross section is made.K 0 and Λ production rates are given in dependence on different inclusive variables. The production properties forK 0′s and Λ′s are discussed in terms of the Quark-Parton-Model. Comparisons with other ν-experiments at higher energies are performed. 相似文献
94.
L. Asch S. Barth F. N. Gygax G. M. Kalvius A. Kratzer F. J. Litterst K. Mattenberger W. Potzel A. Schenck O. Vogt 《Hyperfine Interactions》1986,31(1-4):443-446
UAs has the NaCl structure and undergoes a first order transition into a type I (single k) antiferromagnetic state at 123
K, followed by a second first order transition at 62 K into a type IA (double k) antiferromagnetic structure. μSR spectra
of a powder sample were taken in zero and transverse fields up to 0.3 T. They cover the paramagnetic and the two antiferromagnetic
states. The most significant features of our data are: i) a first increase of relaxation rate below T=180 K; ii) a sudden
jump in both, relaxation rate and frequency shift at T=123 K, together with a small decrease in initial asymmetry (≈15%);
iii) no μ+ spin rotation in zero field in the type I state; iv) an overlay, of 3 spectra in the type IA state. Two of these spectra
show spin rotation in zero field. Their frequencies are clearly temperature dependent. In a transverse field of 5 and 10 mT
the external field adds nearly fully to the internal field.
Work supported in part by the Bundesministerium fur Forschung und Technologie, Federal Republic Germany. 相似文献
95.
B. Kessler N. Müller B. Schmiedeskamp B. Vogt U. Heinzmann 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1990,17(1):11-16
Circularly polarized synchrotron radiation of BESSY has been used to study the angular dependence of the spin polarization of photoelectrons emitted from Xe(√3x√3)R 30° Pd(111). The spin-polarization component along the light helicity varies from +1 for normal emission to ?0.5 for emission angles larger than 45°. The data can be fitted by use of the theory for photoionization of free xenon atoms and yield the dynamical fit parametersA, α, β, ζ for the adsorbate. Good agreement is obtained with the gas phase data. 相似文献
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Steiner's Problem is the “Problem of shortest connectivity”, that means, given a finite set of points in a metric space (X,ρ), search for a network interconnecting these points with minimal length. This shortest network must be a tree and is called a Steiner Minimal Tree (SMT). It may contain vertices different from the points which are to be connected. Such points are called Steiner points. If we do not allow Steiner points, that means, we only connect certain pairs of the given points, we get a tree which is called a Minimum Spanning Tree (MST). Steiner's Problem is very hard as well in combinatorial as in computational sense, but, on the other hand, the determination of an MST is simple. Consequently, we are interested in the greatest lower bound for the ratio between the lengths of these both trees:which is called the Steiner ratio (of (X,ρ)). We look for estimates and exact values for the Steiner ratio in several discrete metric spaces. Particularly, we determine the Steiner ratio for spaces of words, and we estimate the Steiner ratio for specific graphs. 相似文献