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191.
G. Thompson J.A. Gaidos R.L. McIlwain D.H. Miller T.A. Mulera R.B. Willmann 《Nuclear Physics B》1974,69(2):220-236
The missing mass spectrum opposite the proton in a 750 000 picture exposure, 13 GeV/cπ+p bubble chamber experiment, is investigated in two and four pion channels for structures observed or denied by boson spectrometers at the same energy in the reaction π?p→X?p.In the four pion final state the R+ enhancement is observed clearly and the possibility of multi-component mass structure is considered. Treating the phenomenon as one object, cross sections and branching ratios are derived for intermediate quasi two and three body decay modes (ωπ, ??, A2π, ?ππ). The signals in the two pion state and for the neutral state produced opposite Δ++(1231) are also presented and an elasticity is calculated. 相似文献
192.
Oxidation of the isomeric cyclodiphosph(III)azanes, (Me2 NPNBu-t)2, by selenium and by tellurium gives both isomeric monoselenides but only one monotelluride. Variable temperature 1H and 31P NMR studies provide evidence for restricted rotation about the exocyclic PN bonds, and in the telluride, of exchange of tellurium between the phosphorus atoms. 相似文献
193.
The installation of a nuclear magnetic resonance unit in any diagnostic facility involves certain location and environmental requirements. Based on our experience with the FONAR QED 80 system, we have delineated the major factors which must be considered when planning for such an installation. The major requirements are location and space. Suggested layouts for the suite and the control room are included. Certain environmental specifications will vary depending on the location of the facility and the type of unit installed. 相似文献
194.
195.
Measurements of the 50Ti(γ, n) and 50Ti(γ, n0) cross sections have been made in the energy range of the giant dipole resonance (GDR). Assuming the GDR is split into two isospin components, approximated as Lorentzians, a calculation based on statistical decay of the GDR states is consistent with the experimental results. 相似文献
196.
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198.
Khursheed Alam Kenzo Seo James R. Thompson 《Annals of the Institute of Statistical Mathematics》1971,23(1):365-374
Summary A sequential sampling rule is given for selecting the most probable event from a multinomial distribution withk cells. A random number of observations is taken from the given multinomial distribution at each stage of sampling, where
the number is distributed according to a Poisson distribution with mean λ. The sampling is stopped when the count in any cell
is greater than or equal to a given positive integerN. The cell with the highest count is selected for the most probable event. The mathematical analysis of the problem is simplified
as a result of the statistical independence of the cell frequencies due to the randomization of the sample number. The expected
value of the stage when the sampling terminates is decreasing in λ. The sequential sampling scheme in which one observation
is taken at a time until the highest cell count is equal toN, corresponds to λ→0. A table is given showing some properties of the given selection procedure. 相似文献
199.
R.W. Clifft J.B. Dainton E. Gabathuler L.S. Littenberg R. Marshall S.E. Rock J.C. Thompson D.L. Ward G.R. Brookes 《Physics letters. [Part B]》1976,64(2):213-216
A measurement of backward photoproduction of charged pion pairs on protons is reported. The pion pair mass spectrum shows strong ?° and f production. Data are presented on the u and s dependence for ?O and f, together with the decay polarisation for the ?O. 相似文献
200.
Although the automorphism group of a projective plane of order 10, if one exists, must be very small, such a plane could be the derived design of a Steiner system S(3, 12, 112) with a larger group. There are several reasons why the Frobenius group of order 56 is a promising candidate for the latter group. However, in this paper it is shown that there is no S(3, 12, 112) which is fixed by this Frobenius group. 相似文献