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81.
We study the quark and gluon final state in deep inelastic μ-scattering. For a hadron observed at sufficiently large angleθ h with respect to the virtual photon direction, and sufficiently large energy fractionz h , this final state dominates the cross-section. Moreover, at the same time, most events in this regime are due to the fragmentation of the quark. In such cases the position of the gluon in phase space is determined, the quark acting as a trigger for gluon jet detection. We demonstrate that in the rest frame of the final quark and gluon, the gluon is energetic and well separated from quark and target fragments. We study the boost from the lab to this frame, and give expressions for the most probable boost in terms ofθ h andz h . This study should lead to a convenient visualization of the gluon jet. 相似文献
82.
Milena P. Stojanova 《Constructive Approximation》1988,4(1):435-445
Generalizing the Walsh theorem, E. B. Saff, A. Sharma, and R. S. Varga showed that there is a close relation between the rational interpolants in roots of unity and Padé approximants of certain meromorphic functions. The purpose of this paper is to extend this result, replacing the Padé approximant with other rational functions so as to obtain a larger region of equiconvergence. 相似文献
83.
84.
The sorption and permeation of carbon dioxide gas in miscible blends of poly(phenylene oxide) and polystyrene was measured as a function of pressure at 35°C over the entire range of blend compositions. The results are well described quantitatively by the dual sorption and dual mobility models developed for glassy polymers. The Henry's law sorption parameter was analyzed by the Flory—Huggins theory of ternary mixtures to obtain an interaction parameter which quantifies the exothermic heat of mixing for this blend system. The Langmuir capacity term was successfully related to the unrelaxed volume of the glassy blends. Transport properties of the blends were found to lie well below predictions based on simple additivity which is consistent with the strong interaction between the two polymers. 相似文献
85.
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88.
We study the finite-size effects associated with the appearance of a light, i.e. Goldstone, particle in the Kogut-Susskind lattice gauge theory. We analytically study the order parameter and the two-meson propagator in the strong coupling limit on a finite lattice. We give their explicit interpolations between the broken phase of the infinite-volume limit and the symmetric one of the finite system. We argue that the results obtained in the strong coupling limit are more general. 相似文献
89.
In this work, two narrow-bore capillary columns with different internal diameters (I.D.) 0.15 mm (15 m length, 0.15 microm film thickness) and 0.10 mm (10 m length, 0.10 microm film thickness) with the same stationary phase (5% diphenyl 95% dimethylsiloxane), phase ratio and separation power were compared with regard to their advantages, practical limitations and applicability in fast GC on commercially available instrumentation. The column comparison concerns fast GC method development, speed and separation efficiency, the sample transfer into the column utilizing split and splitless inlet, sample capacity, detection (analysing compounds of a wide range of polarities and volatilities--even n-alkanes C16-C28 and selected pesticides) and ruggedness (in the field of ultratrace analysis of pesticide residues in real matrix). Under conditions corresponding to speed/separation efficiency trade-off 0.10 mm I.D. versus 0.15 mm I.D. column provides a speed gain of 1.74, but all other parameters investigated were better for the 0.15 mm I.D. column concerning more efficient sample transfer from inlet to the column using splitless injection, no discrimination with split injection. Better sample capacity (three times higher for the 0.15 mm than for the 0.10 mm I.D. column) resulted in improved ruggedness and simpler fast GC-MS method development. 相似文献
90.
Andrew M. Raim Nagaraj K. Neerchal Jorge G. Morel 《Journal of computational and graphical statistics》2018,27(3):587-601
Finite mixture distributions arise in sampling a heterogeneous population. Data drawn from such a population will exhibit extra variability relative to any single subpopulation. Statistical models based on finite mixtures can assist in the analysis of categorical and count outcomes when standard generalized linear models (GLMs) cannot adequately express variability observed in the data. We propose an extension of GLMs where the response follows a finite mixture distribution and the regression of interest is linked to the mixture’s mean. This approach may be preferred over a finite mixture of regressions when the population mean is of interest; here, only one regression must be specified and interpreted in the analysis. A technical challenge is that the mixture’s mean is a composite parameter that does not appear explicitly in the density. The proposed model maintains its link to the regression through a certain random effects structure and is completely likelihood-based. We consider typical GLM cases where means are either real-valued, constrained to be positive, or constrained to be on the unit interval. The resulting model is applied to two example datasets through Bayesian analysis. Supporting the extra variation is seen to improve residual plots and produce widened prediction intervals reflecting the uncertainty. Supplementary materials for this article are available online. 相似文献