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91.
92.
Parton distribution functions consistent with neutrino and muon deep inelastic scattering as well as Drell-Yan pair production results have been extracted. This analysis incorporates experimental systematic errors which are the dominant errors in recent deep inelastic scattering experiments. The dependence of the results on factors such as kinematic cuts in the data, heavy target corrections, and choice of initial functional form are also explored. The form adopted is motivated by perturbative QCD and particularly useful in exploring the small-x extrapolation of the distributions. This is crucial for studying the range of predictions for Collider, HERA, and SSC/LHC cross sections. Representative distribution function sets are presented in a very compact parametrized form both in the DIS and MS-bar renormalization schemes.This work is partially supported by the National Science Foundation under Grant No. PHY89-05161. This work was also supported by Argonne National Laboratory during the 1988–89 academic year when the author was on Sabbatical leave at the Laboratory from IIT 相似文献
93.
The transverse momentum dependence of the parton distribution function and the Drell-Yan cross section is studied in detail in the asymptotically free scalar field theory in six dimensions. In the context of the renormalization group approach of Collins, particular attention is devoted to the transition between the small qT formula (due to multe-quanta effects) and the large qT formula (due to single hard-quantum emission). The calculation represents a case study of the application of the renormalization group method and provides a guide to the corresponding study in QCD. 相似文献
94.
95.
N. Chan Tung Y. Caratini C. D'Anterroches J. L. Buevoz 《Applied Physics A: Materials Science & Processing》1988,47(3):237-247
Rapid Thermal oxidation (RTO) of silicon has been investigated in the temperature range 1000° to 1250°C for an oxidation time of 5 to 60 s. The fairly extensive kinetics data show that linear growth occurs with an activation energyE
a of 1.4 eV. Rapid thermal nitridation of SiO2 (96 Å) has been performed at three different temperatures: 1150°, 1200°, and 1250°C for a nitridation time up to 150 s. The characteristics of both materials have been investigated by capacitance-voltage, current-voltage, high resolution transmission electron microscopy and Auger spectroscopy. The results will be discussed with special emphasis on breakdown field statistics. The influence of Rapid Thermal Annealing (RTA) on the characteristics of both oxide and nitrided oxide will also be presented. A simulation model of a rapid thermal processing machine is presented with particular attention to the formation of slip lines. The theoretical results are in good agreement with those obtained experimentally. 相似文献
96.
L. H. Tung 《Journal of Polymer Science.Polymer Physics》1969,7(1):47-55
A method of determining the distribution of branching in polydisperse polymer samples is proposed. This method uses data from concurrent gel permeation chromatography and sedimentation-velocity experiments. Tedious fractionation, which must precede other methods of determining long-chain branching, is eliminated. An example of use of the method on the data of a sample of styrene–divinylbenzene copolymer is given. 相似文献
97.
98.
The Nachtmann moments of deep inelastic scattering structure functions are required by kinematics to contain a so far neglected threshold factor which is dependent on both n and q2. Its presence significantly affects the “moment analysis” in the usual QCD phenomenology and it resolves the difficulties connected with improper threshold behavior of the “ξ-scaling” analysis of structure functions. 相似文献
99.
Graft distribution functions have been derived from random grafting statistics. Among the functions, the weight fraction of ungrafted backbone chains, the molecular weight distribution of the ungrafted backbone chains and the GPC apparent molecular weight distribution of the graft copolymer have been found to agree with experimental values determined for a graft copolymer system in which grafting was expected to be random. The other functions, which are not directly measurable, are therefore probably also correct. In analytical work the entire set of graft distribution functions may be computed for a graft copolymer system from the following experimental data: (1) molecular weight distribution of the starting backbone chains; (2) the chemical composition of the mixture of the graft copolymer and ungrafted backbone; (3) the graft side-chain molecular weight distribution, which may be assumed to be identical to that of the ungrafted homopolymer separable from the reaction mixture. 相似文献
100.