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61.
We describe a method for using extensive air shower data to determine whether a Feynman scaling limit exists in the central region for inclusive cross sections. Preliminary analysis suggests that the shower muon to electron ratio is more consistent with a power law increase of pion multiplicity with energy than with the logarithmic multiplicity increase characteristic of a scaling limit, but an analysis of the intra-nuclear cascade is required to reach a firm conclusion. 相似文献
62.
63.
As a result of research, the propagation characteristics of optical waveguides are becoming well enough understood for system evaluation. In this paper material and structural properties of the waveguide are related to measurements made on present experimental waveguides. Among the conclusions drawn from this work are that intermodal dispersion provides the dominant pulse broadening contribution but that this has been reduced to the nanosecond region by radial index gradient control. For present source spectral bandwidths, material dispersion is not a major contribution to pulse broadening. Waveguides up to 3 km long can be made with negligible intrinsic mode coupling. This gives rise to the possibility of either internal or external control to increase the information carrying capacity of the waveguide. External control has already been demonstrated. However, additional work is required to make this practical. 相似文献
64.
H. Braun D. Evrard A. Fridman J. -P. Gerber A. Givernaud J. Grunhaus R. Kahn G. Maurer A. Michalon B. Schiby R. Strub C. Voltolini 《Zeitschrift für Physik A Hadrons and Nuclei》1971,247(2):107-116
A study of a 150000-picture exposure of ¯pd at 5.5 GeV/c yielded 152 events satisfying the hypothesis ¯pd→p s π+2π?π0. For the events with proton spectator in the momentum range 100–280 MeV/c we obtained the cross section of 0.11±0.02 mb. Assuming the validity of the impulse approximation we estimate a cross section of 0.43±0.06 mb for the reaction ¯pn→ π+2π?π0. The rate for single ? meson production and an upper limit for double ? production are given. A modified multiperipheral Regge model was used in order to describe the general features of the data. 相似文献
65.
In this paper stability properties of the extremal value function are studied for infinite-dimensional nonlinear optimization problems with differentiable perturbations in the objective function and in the constraints. In particular, upper and lower bounds for the directional derivative of the extremal value function as well as necessary and sufficient conditions for the existence of the directional derivative are given. 相似文献
66.
Donald Maurer 《Journal of Number Theory》1973,5(5):379-384
Let F be the rational field or a p-adic field, and let K an algebraic number field over F. If ω1,…, ωn is an integral basis for the ring L of integers in K, then the quadratic form Q whose matrix is (traceK∥F(ωiωj)) has integral coefficients, and is called an integral trace-form. Q is determined by K up to integral equivalence. The purpose of this paper is to show that the genus of Q determines the ramification of primes in K. 相似文献
67.
Stephen B Maurer 《Journal of Combinatorial Theory, Series B》1973,15(2):121-145
Several graph-theoretic notions applied to matroid basis graphs in the preceding paper are now tied more specifically to aspects of matroids themselves. Factorizations of basis graphs and disconnections of neighborhood subgraphs are related to matroid separations. Matroids are characterized whose basis graphs have only one or two of the three types of common neighbor subgraphs. The notion of leveling is generalized and related to matroid sums, minors, and duals. Also, the problem of characterizing regular and graphic matroids through their basis graphs is discussed. Throughout, many results are obtained quite easily with the aid of certain pseudo-combivalence systems of 0–1 matrices. 相似文献
68.
69.
A model to describe vapor-liquid equilibrium (VLE) and solid-liquid equilibrium (SLE) in the ammonia-phosphoric acid-water system is developed. The model takes into account chemical reactions as well as physical interactions. Using interaction parameters and solubility contants as determined from experimental data on VLE and SLE, the model is capable of describing the phase behavior in this extremely complex system over a wide range of composition.Dedicated to Prof. Dr.-Ing. G. Ernst on the occasion of his 60th birthday. 相似文献
70.
C.R. Ottermann G. Köbschall K. Maurer K. Röhrich Ch. Schmitt V.H. Walther 《Nuclear Physics A》1985,436(4):688-698
The cross sections for elastic electron scattering from 3He and 4He were measured for the momentum transfer range from 0.45–2.0 fm?1. The cross sections were separated into their longitudinal (charge) and transverse (magnetic) contributions using the Rosenbluth formula. The charge and magnetic form factors were obtained model-independently.The rms charge radii were found to be 1.671 (14) fm for 4He and 1.976 (15) fm for 3He, and the magnetic rms radius of 3He is 1.99 (6) fm. The mis charge radius for 4He is in excellent agreement with the latest muonic data.Comparison of the form factors was made with Faddeev three-body calculations using realistic two-body NN interactions. At present the theoretical calculation is not able to reproduce the experimental data. 相似文献