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91.
V.A. Khoze A.D. Martin M.G. Ryskin 《The European Physical Journal C - Particles and Fields》2002,23(2):311-327
We study the double-diffractive production of various heavy systems (e.g. Higgs, dijet, and SUSY particles) at LHC and Tevatron collider energies. In each case we compute the probability that the rapidity gaps,
which occur on either side of the produced system, survive the effects of soft rescattering and QCD bremsstrahlung effects.
We calculate both the luminosity for different production mechanisms, and a wide variety of subprocess cross sections. The
results allow numerical predictions to be readily made for the cross sections of all these processes at the LHC and the Tevatron
collider. For example, we predict that the cross section for the exclusive double-diffractive production of a 120 GeV Higgs boson at the LHC is about 3 fb, and that the QCD background in the decay mode is about 4 times smaller than the Higgs signal if the experimental missing-mass resolution is 1 GeV. For completeness
we also discuss production via or WW fusion.
Received: 7 November 2001 / Revised version: 11 December 2001 / Published online: 25 January 2002 相似文献
92.
We construct a correspondence between the set of partitions of a finite set M and the set of pairs of walks to the same vertex on a graph giving the Bratteli diagram of the partition algebra on M. This is the precise analogue of the correspondence between the set of permutations of a finite set and the set of pairs of Young tableaux of the same shape, called the Robinson–Schensted correspondence. 相似文献
93.
Ricardo García-Pelayo Iván Salazar William C. Schieve 《Journal of statistical physics》1993,72(1-2):167-187
An analytically solvable model for sand avalanches of noninteracting grains of sand, based on the Chapman-Kolmogorov equations, is presented. For a single avalanche, distributions of lifetimes, sizes of overflows and avalanches, and correlation functions are calculated. Some of these are exponentials, some are power laws. Spatially homogeneous distributions of avalanches are also studied. Computer simulations of avalanches of interacting grains of sand are compared to the solutions to the Chapman-Kolmogorov equations. We find that within the range of parameters explored in the simulation, the approximation of noninteracting grains of sand is a good one. 相似文献
94.
X-ray photoelectron and Auger spectroscopies were used to examine surface bonding and overlayer growth during palladium and copper deposition onto films of fullerene, C60 The results were consistent with metal cluster formation on C60. The observed positive core electron binding energy shifts in small metallic clusters supported on C60 were shown to originate in metal-fullerene interaction accompanied by charge transfer. Palladium-fullerene intermixing at temperatures as low as ss 50°C was observed for small Pd coverages. 相似文献
95.
Summary In this paper, we develop a framework suitable for performing a multiresolution analysis using univariate spline spaces of arbitrary degree and with non-uniform knot-sequences. To this end, we show, among other things, the existence of compactly supported prewavelets and of prewavelets that are globally supported, but decay exponentially. In each case we obtain a decomposition of a fine spline space as a sum of a coarse spline space plus a spline space spanned by prewavelets. 相似文献
96.
Summary We prove convergence and error estimates in Sobolev spaces for the collocation method with tensor product splines for strongly elliptic pseudodifferential equations on the torus. Examples of applications include elliptic partial differential equations with periodic boundary conditions but also the classical boundary integral operators of potential theory on torus-shaped domains in three or more dimensions. For odd-degree splines, we prove convergence of nodal collocation for any strongly elliptic operator. For even-degree splines and midpoint collocation, we find an additional condition for the convergence which is satisfied for the classical boundary integral operators. Our analysis is a generalization to higher dimensions of the corresponding analysis of Arnold and Wendland [4]. 相似文献
97.
98.
F. Rubio F. García H. D. Burrows A. A. C. C. Pais A. J. M. Valente M. J. Tapia J. M. García 《Journal of polymer science. Part A, Polymer chemistry》2007,45(9):1788-1799
The interaction between trivalent lanthanide ions and poly(1,4,7,10,13‐pentaoxacyclopentadecan‐2‐yl‐methyl methacrylate), PCR5, in aqueous solution and in the solid state have been studied. In aqueous solution, evidence of a weak interaction between the lanthanides and PCR5 comes from the small red shift of the Ce(III) emission spectra and the slight broadening of the Gd(III) EPR spectra. From the Tb(III) lifetimes in the presence of H2O and D2O the loss of one or two water coordinated molecules is confirmed when Tb(III) is bound to PCR5. An association constant of the order of 200 M?1 was obtained for a 1:1 (lanthanide:15‐crown‐5) complex from the shift of the polymer NMR signals induced by Tb(III). A similar association constant is obtained from the differences of the molar conductivity of Ce(III) solution at various concentrations in presence and absence of PCR5. When Tb(III) is adsorbed on PCR5 membranes, lifetime experiments in H2O and D2O confirm the loss of 5 or 6 water coordinated molecules indicating that in solid state the lanthanide(III)‐PCR5 interaction is stronger than in solution. The adsorption of Ce(III) in PCR5 membranes shows a Langmuir type isotherm, from which an equilibrium constant of 39 M?1 has been calculated. SEM shows that the membrane morphology is not much affected by lanthanide adsorption. Support for lanthanide ion–crown interactions comes from ab initio calculations on 15‐crown‐5/La(III) complex. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1788–1799, 2007 相似文献
99.
100.
In this paper, we apply a three-stage-DEA model to the Spanish Professional Football League, which means separating the teams’
economic behaviour into three components: operating efficiency—of the offence and defence—athletic or operating effectiveness,
and social effectiveness. The results showed that the technical inefficiency of the defence is greater than that of the offence,
both being caused by aspects linked to the poor management of players’ abilities and by the football team’s size. Teams showed
a favourable evolution of their offensive and defensive efficiency during the 2004/2005 season and to a lesser extent in the
season before. The point system assigned by the professional football league regulations evaluates the teams’ athletic effectiveness,
but we detected that the teams with the most experience perform athletically in a more effective manner. Their social effectiveness
is strongly related to the level of play in itself and to factors linked to their PFL ranking: participation in international
competitions for important football teams; or the struggle of minor football teams to stay in the first division. 相似文献