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901.
902.
We study photoproduction of jets and heavy flavors in a polarized collider mode of HERA and in polarized ep collisions at √S ≈ GeV. We examine the sensitivity of the cross sections and their asymmetries to the proton’s polarized gluon distribution and to the completely unknown parton distributions of longitudinally polarized photons. 相似文献
903.
C. Boldrighini R.A. Minlos A. Pellegrinotti 《Communications in Mathematical Physics》1997,189(2):533-557
We consider a general model of directed polymers on the lattice , weakly coupled to a random environment. We prove that the central limit theorem holds almost surely for the discrete time
random walk X
T
associated to the polymer. Moreover we show that the random corrections to the cumulants of X
T
are finite, starting from some dimension depending on the index of the cumulants, and that there are corresponding random
corrections of order , , in the asymptotic expansion of the expectations of smooth functions of X
T
. Full proofs are carried out for the first two cumulants. We finally prove a kind of local theorem
showing that the ratio of the probabilities of the events to the corresponding probabilities with no randomness, in the region of “moderate” deviations from the average drift bT, are, for almost all choices of the environment, uniformly close, as , to a functional of the environment “as seen from (T,y)$”.
Received: 14 October 1996 / Accepted: 28 March 1997 相似文献
904.
Consideration is given to the special features of the excitation of spectra of metals (Ag, Au, Fe, Hg, Pt, and Sb) that manifest
themselves in investigating spectral sources with combined glow discharge (glow discharge and capillary discharge). It is
established that the proposed method for introducing a substance into a plasma makes it possible to realize two fundamentally
different regimes: without evaporation and with complete evaporation and matrix atomization. It is shown that a spectral source
of combined glow discharge with a nonequilibrium plasma has significant advantages for the most important analytical characteristics
over quasi-equilibrium combined discharge at atmospheric pressure. The gold and platinum sensitivity in combined glow discharge
is 10−7%, and the reproducibility of spectral determinations is 0.001–0.100, depending on the measurement range. A fractional separation
of elements that makes it possible to analyze the phase composition of substances, particularly metals, with high sensitivity
is revealed in glow discharge.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 2, pp. 143–147, March–April, 1997. 相似文献
905.
We investigate a new interpretation for the Navier-Stokes corrections to the hydrodynamic equation of asymmetric interacting particle systems. We consider a system that starts from a measure associated with a profile that is constant along the drift direction. We show that under diffusive scaling the macroscopic behavior of the process is described by a nonlinear parabolic equation whose diffusion coefficient coincides with the diffusion coefficient of the hydrodynamic equation of the symmetric version of the process. 相似文献
906.
A. V. Razin 《Radiophysics and Quantum Electronics》1997,40(4):274-282
Using the contour integration method, we solved the problem on the transient radiation of acoustic waves by a mass-production
source which moves uniformly in a gas in the direction normal to the interface of homogeneous gaseous and elastic half-spaces
and vanishes at the moment of the solid surface contact. Asymptotic formulas are derived for the transient radiation field
which are valid at the fronts of spherical and lateral waves. An exact analytical expression is obtained for the transient
radiation field at observation points in the source trajectory. The total internal reflection effects in the transient radiation
of sound are analyzed.
Radiophysical Research Institute, Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika,
Vol. 40, No. 4, pp. 420–431, April, 1997. 相似文献
907.
Y. A. Coutinho J. A. Martins Simões C. M. Porto 《Zeitschrift fur Physik C Particles and Fields》1997,73(4):705-709
In this paper we investigate the effects of heavy Majorana neutrinos in the reaction e + e ? → W + W ?. We consider neutrino masses in the 1–10 TeV region. We show that at LEP II and NLC energies it is possible to use this processes to verify indirect evidence of heavy neutral particles with mixing angles of the order sin2 α = 0.01. We discuss the unitarity restrictions that can be obtained for vector singlet and fermion-mirror-fermion models. 相似文献
908.
It is shown that the potential perturbation that shifts a chosen standing wave in space is a block of potential barrier and well for every wave bump between neighbouring knots. The algorithms shifting the range of the primary localization of a chosen bound state in a potential well of finite width are as well applicable to the scattering functions if states of the continuous spectrum are considered as bound states normalized to unity but distributed on an infinite interval with vanishing density. The potential perturbations of the same type on the half-axis concentrate the scattering wave at the origin, thus creating a bound state embedded into the continuous spectrum (zero width resonance). 相似文献
909.
L. Bugliaro J. Fröhlich G.M. Graf J. Stubbe C. Fefferman 《Communications in Mathematical Physics》1997,187(3):567-582
A Lieb-Thirring-Sobolev type inequality for Pauli Hamiltonians with magnetic fields is derived. The bound is in terms of an
effective field, whose energy is comparable to that of the magnetic field itself. An application to the stability of matter
in magnetic fields is given.
Received: 19 September 1996 / Accepted: 3 January 1997 相似文献
910.
Applying the mass shell condition forq-deformed open and closed strings, new critical space-time dimensions are derived.
Supported by the Algerian Ministry of High Education and Research under contract NoD2501/17/01/93.
Permanent address. 相似文献