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91.
K. Böckmann H.G. Heilmann U. Idschok P. Kobe F. Selonke V. Blobel H. Fesefeldt B. Hellwig D. Mönkemeyer H. Franz P. Freund W. Schrankel 《Nuclear Physics B》1974,81(1):45-60
The reaction pp → nucleon + nucleon + pion at 12 and 24 GeV/c is analyzed in terms of the isospin amplitudes for the production of the (Nπ) system. The energy dependence of the amplitude is weak, while the contribution shows the strong energy dependence known from meson exchange reactions. The slope parameter B of the dσ/dt′ distributions of the contribution is a strong function of the (Nπ) mass, decreasing sharply from about 12 GeV?2 at threshold to about 4 GeV?2 above 1700 MeV. Comparing our results for the cross section with those of similar investigations in πp and Kp reactions, we find that factorisation is valid within experimental errors. The results support the conclusion that the contribution is dominated by diffraction dissociation of the proton. 相似文献
92.
V. Blobel H. Fesefeldt P. Freund C. Geich-Gimbel B. Hellwig U. Idschok J.W. Lamsa D. Lüers D. Mönkemeyer N. Schmitz B. Schröder B.M. Schwarzschild 《Nuclear Physics B》1975,88(1):18-40
In this paper we study correlations in multiparticle final states from pp interactions at 12 and 24 GeV/c. In an attempt to distinguish true dynamical correlations from the consequences of kinematics together with PT damping and the leading-particle effect, we compare the data with an independent-emission model which reproduces the single-particle spectra and also with a model that simulates a fragmentation mechanism. We investigate the forward-backward particle configurations and in particular the multiplicity imbalance and charge transfer, defining forward-backward by the largest rapidity gap as well as simply by c.m.s. hemispheres. We also study clustering by looking at distributions of the dispersions in longitudinal rapidity. From the comparison of the data with the models we find clear evidence for dynamical correlations of a sort one would expect from fragmentation-type mechanisms. We also find indications of non-fragmentation formation of neutral meson clusters. 相似文献
93.
94.
Maria Freund 《Fresenius' Journal of Analytical Chemistry》1963,194(4):314
Ohne Zusammenfassung 相似文献
95.
We are concerned with the problem of finding the polynomial with minimal uniform norm on
among all polynomials of degree at most n and normalized to be 1 at c. Here,
is a given ellipse with both foci on the real axis and c is a given real point not contained in
. Problems of this type arise in certain iterative matrix computations, and, in this context, it is generally believed and widely referenced that suitably normalized Chebyshev polynomials are optimal for such constrained approximation problems. In this work, we show that this is not true in general. Moreover, we derive sufficient conditions which guarantee that Chebyshev polynomials are optimal. Also, some numerical examples are presented. 相似文献
96.
97.
Using a CO2 laser, Stark shifted resonances have been measured for the CF stretching fundamental (ν3) of FCN near 9.3 μm, and for two nearby “hot” bands. The band centers measured are 1076.492007 ± 0.000013 cm?1 for 0001-0000, 1085.741046 ± 0.000050 cm?1 for 0111-0110, and 1091.16222 ± 0.00015 cm?1 for 0201-0200. The ground state dipole moment of FCN is found to be 2.1203 ± 0.0010 D and dipole moments are also given for the other states observed. Values are given for the rotational constant and l-doubling constant for the 0111 state. 相似文献
98.
Isotopically selective dissociation of MoF6 has been induced by irradiating low pressure samples of MoF6 with intense CO2 laser radiation. Several frequencies within the weak υ3 + υ5 combination band were employed. The isotopic selectivity was about 1% per mass unit which reflects the small isotope shifts, and the reaction yield was substantially less than for similar experiments with SF6. 相似文献
99.
Thomas Freund 《Advances in colloid and interface science》1979,11(1):43-66
Tribo-electrification is a process in which two bodies are contacted and separated with the result that each body becomes electrically charged. The connection between chemistry and charging is illustrated by describing, in some detail, contacting experiments between mercury and insulating organic materials after various chemical treatments of the organic surface. Introductions to selected topics are presented; principles for methods of measurment, some experimental results, an electroni model involving surface states for charging between a metal and an insulator, some factors limiting chargin, and some qualitative correltaions with the macroscopic compositions of the materials. 相似文献
100.
Maria Freund 《Fresenius' Journal of Analytical Chemistry》1963,192(2):319-320
Ohne Zusammenfassung 相似文献