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991.
992.
A. Ferrer D. Treille P. Rivet A. Volte P. Benkheiri G. De Rosny A. Rougé B. Bouquet B. DAlmagne H. Nguyen P. Petroff F. Richard P. Roudeau J. Six H. Yoshida 《Nuclear Physics B》1981,178(3):373-391
We have analysed about 85 000 fast Λ0 events, obtained in a fast proton triggered experiment performed at the CERN-Ω spectrometer at 9 and 12 GeV/c incident π? beam. Nearly 2500 Λ0K+π? events have been isolated. We find strong production of quasi-two-body processes and consistent with u-channel hyperon exchange. Results on Λ0 polarization, K10 decay parameters and differential cross sections are given for and final states. A comparison is made with the associated backward production seen in the four-prong reaction π?p→pK?K+π? obtained in the same experiment. 相似文献
993.
994.
Gerald M. Rosen Frederick Q. Gemmill Edgar O. Snoke Frank D. Popp 《Journal of heterocyclic chemistry》1975,12(4):619-622
The hydrazides of benzoic, phenyacetic, and 3-phenylpropionic acids react with an acidic solution of formaldehyde to give 15 . Similar treatment of the corresponding methylhydrazides gave 16 . The ethers 15 can be cleaved to give, after methylation, 16 . Spectral data for 15 and 16 are presented. 相似文献
995.
The representation of a nucleon bound state by a single Hankel function is generalised such that the bound state is expanded as a linear combination of Hankel functions of the samel-value. The singularity at the origin due to the use of Hankel functions is removed. The arguments and coefficients of the expansion are determined by a variational method. 相似文献
996.
997.
It is shown that the left-right symmetric gauge models based on the group = SU(2)L × SU(2)R × U(1)L × U(1)R can accommodate quite naturally the results of the recent SLAC experiment concerning parity violation in neutral currents. The possibility of finding a light neutral gauge boson in the PETRA-PEP energy range remains particularly interesting. 相似文献
998.
The analysis of the element pattern in an array of waveguide elements on a cone is approached by systematically exploiting the geometrical symmetry of the structure. The method consists of decomposing the arbitrary array excitation into fundamental excitations (eigenexcitations) for which the solution of the electromagnetic problem is simpler than in the general case. Following Bailin and Silver, the fields external to the cone are represented as a superposition of modes TE and TM to the radial direction. For each eigenexcitation the fields in the waveguide elements are represented as a superposition of normal waveguide modes. The enforcement of the continuity of the electromagnetic fields at the conical interface provides complete information about the radiation from the elements and the reflection coefficients of the modes in the waveguide. The array element pattern is obtained by the superposition, with suitable weights, of the patterns of the eigenexcitations. The communication presents the computational procedures followed to evaluate with high speed and precision the roots of the Legendre functions necessary to represent the fields external to the conical structure. Numerical results for the realized element patterns of a particular conical array are presented in the final section. 相似文献
999.
We report results obtained from thermally stimulated current and capacitance measurements of metal-SiO-metal structures having different metals for the electrodes. Dependence of relaxed charge on the polarized electrode suggests the existence of space charge near the metal-insulator interface. The measurements of capacitance under superimposed DC voltages support this interpretation and show that space charge is not negligible at high fields. The density of lacalised states evaluated from the data is of the order of 1017 cm?3 相似文献
1000.
Factorization methods used in shell-model approaches to nuclear reactions provide a good starting point for perturbative treatments of direct coupling. General algebraic equations are given for zero and higher orders. Problems of convergence of the Born series are tested with a soluble model. It is shown that the zero-order approximation is quite good. First- and second-order corrections are calculated and exhibit a rapid convergence. The influence of parameters entering in factorization formulae is discussed. 相似文献