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931.
The results of Monte Carlo simulations of the beta dose rate to enamel are presented. The dose rates are the most comprehensive to date, incorporating the beta spectrum from 21 different radionuclides, all internal conversion and Auger electrons, the majority of the bremsstrahlung radiation, effects due to radon loss in the uranium series, and variations in the moisture content of the sediment. Applications to a new dating technique in archaeology using electron spin resonance and beta-gradient isochrons are discussed. 相似文献
932.
933.
934.
935.
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
936.
Ivonin I. V. Krasil'nikova L. M. Lavrent'eva L. G. Porokhovnichenko L. P. 《Russian Physics Journal》2002,45(5):493-497
Experimental proofs of asymmetric trapping of atoms at the growth step in vapor-phase epitaxy of gallium arsenide in the GaAs–AsCl3–H2 system are given. The data obtained confirm the important role of the surface diffusion mass transfer in the growth of epitaxial GaAs layers on vicinals in the neighborhood of (111)A. The effective diffusion length is estimated. 相似文献
937.
V.I. Fernández A. Iucci C.M. Naón 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,30(1):53-56
We present an extension of the Tomonaga-Luttinger model in which left and right-moving particles have different Fermi velocities.
We derive expressions for one-particle Green's functions, momentum-distributions, density of states, charge compressibility
and conductivity as functions of both the velocity difference ε and the strength of the interaction β. This allows us to identify
a novel restricted region in the parameter space in which the system keeps the main features of a Luttinger liquid but with
an unusual behavior of the density of states and the static charge compressibility κ. In particular κ diverges on the boundary
of the restricted region, indicating the occurrence of a phase transition.
Received 20 May 2002 / Received in final form 23 August 2002 Published online 19 November 2002 相似文献
938.
The energy characteristics of an XeCl exciplex lamp with planar construction pumped by a low-pressure gas discharge are investigated
experimentally. When a discharge gap of width 2 cm and a Xe-Cl2 mixture were used, average radiation powers up to 20 mW were obtained in the wavelength interval 200–380 nm at efficiencies
of ∼0.4%. In this case the total efficiency of radiation into an angle of 4π exceeded 4%. It is shown that increasing the working pressure and using low discharge currents can lead to “point” radiation
sources.
Zh. Tekh. Fiz. 67, 43–46 (December 1997) 相似文献
939.
S. Moss de Oliveira P. M. C. de Oliveira F. C. de Sá Barreto 《Journal of statistical physics》1995,78(5-6):1619-1627
Using the finite-size scaling renormalization group, we obtain the two-dimensional flow diagram of the Blume-Capel model forS=1 andS=3/2. In the first case our results are similar to those of mean-field theory, which predicts the existence of first- and second-order transitions with a tricritical point. In the second case, however, our results are different. While we obtain in theS=1 case a phase diagram presenting a multicritical point, the mean-field approach predicts only a second-order transition and a critical endpoint. 相似文献
940.
We propose a way of modifying the mathematical model of the nondestructive theoretical-experimental method of determining the residual stresses for a specific collection of technological conditions for welding two cylindrical glass shells. The method is based on the general theory of boundary-value problems for ordinary differential equations.Translated fromMatematicheskie Metody i Fiziko-Mekhanicheskie Polya, Issue 33, 1991, pp. 69–73. 相似文献