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91.
Artuso M Blusk S Butt J Li J Menaa N Mountain R Nisar S Randrianarivony K Sia R Skwarnicki T Stone S Wang JC Zhang K Bonvicini G Cinabro D Dubrovin M Lincoln A Asner DM Edwards KW Naik P Briere RA Ferguson T Tatishvili G Vogel H Watkins ME Rosner JL Adam NE Alexander JP Cassel DG Duboscq JE Ehrlich R Fields L Galik RS Gibbons L Gray R Gray SW Hartill DL Heltsley BK Hertz D Jones CD Kandaswamy J Kreinick DL Kuznetsov VE Mahlke-Krüger H Mohapatra D Onyisi PU Patterson JR Peterson D Pivarski J 《Physical review letters》2007,99(19):191801
Using a 281 pb{-1} data sample collected at the psi(3770) with the CLEO-c detector, we present the first absolute branching fraction measurement of the decay D0-->K(-)pi(+)pi(-)e(+)nu(e) at a statistical significance of about 4.0 standard deviations. We find 10 candidates consistent with the decay D0-->K(-)pi(+)pi(-)e(+)nu(e). The probability that a background fluctuation accounts for this signal is less than 4.1 x 10{-5}. We find B(D0-->K(-)pi(+)pi(-)e(+)nu(e)) = [2.8{-1.1}{+1.4}(stat)+/-0.3(syst)]x10{-4}. By restricting the invariant mass of the hadronic system to be consistent with K1(1270), we obtain the product of branching fractions B(D{0}-->K{1}{-}(1270)e{+}nu{e})xB(K1-(1270)-->K{-}pi{+}pi{-})=[2.5{-1.0}{+1.3}(stat)+/-0.2(syst)]x10{-4}. Using B(K1-(1270)-->K{-}pi{+}pi{-})=(33+/-3)%, we obtain B(D{0}-->K{1}{-}(1270)e{+}nu{e})=[7.6{-3.0}{+4.1}(stat)+/-0.6(syst)+/-0.7]x10{-4}. The last error accounts for the uncertainties in the measured K1-(1270)-->K{-}pi{+}pi{-} branching fractions. 相似文献
92.
93.
Andrey V. Kuznetsov 《Central European Journal of Physics》2011,9(1):146-156
This paper formulates a four kinetic state model for fast axonal transport. The paper further develops the Smith-Simmons model
that is based on equations governing intracellular molecular-motor-assisted transport; these equations are extended by considering
four rather than three kinetic states for organelles. The model considers plus-end and minus-end-oriented organelles that
can be either free (suspended in the cytosol) or attached to microtubules (MTs) (in the latter case organelles are transported
by molecular motors). The paper then develops a method for uncoupling differential equations of the proposed model. A perturbation
solution of this problem is obtained. The effect of transition between plus-end-oriented and minus-end oriented organelles
is discussed. The accuracy of the obtained perturbation solution is evaluated by comparing the zero-order and the first-order
results with a high-accuracy numerical solution. 相似文献
94.
Yu. A. Kuznetsov 《Computational Mathematics and Modeling》1997,8(1):49-61
The article presents some results on solvability and qualitative properties of solutions of the abstract Cauchy problem for
a new class of nonlinear equations of evolution in Banach spaces. These results provide a unified framework for the analysis
of a wide range of applied problems. Some applications to nonlinear mathematical problems of nuclear reactor dynamics are
suggested.
Supported by a grant from the Ministry of Science, Higher Education, and Technical Policy of the Russian Federation as part
of the program, “Nonlinear Dynamic Systems: Qualitative Analysis and Control.”
Translated from Nelineinye Dinamicheskie Sistemy: Kachestvennyi Analiz i Upravlenie — Sbornik Trudov, No. 2, pp. 76–90, 1994. 相似文献
95.
V. Yu. Alexakhin M. I. Gostkin K. K. Gudima M. P. Ivanov A. Kugler I. V. Kuznetsov S. I. Merzlyakov C. L. Morris E. A. Pasyuk Yu. E. Penionzhkevich S. Yu. Porokhovoy Yu. G. Sobolev V. D. Toneev 《Physics of Atomic Nuclei》2000,63(10):1673-1678
The inclusive energy spectra and multiplicities of p, d, and t from the reactions 14N(Ag, X), X=p, d, t at E/A=52 MeV are measured. The experimental data are compared with the results obtained within the Dubna version of the cascade model and are analyzed on the basis of the moving-source model. 相似文献
96.
Yu. A. Bykovskii V. A. Karavanskii G. E. Kotkovskii M. B. Kuznetsov A. A. Chistyakov A. A. Lomov S. A. Gavrilov 《Journal of Experimental and Theoretical Physics》2000,90(1):121-128
Photoprocesses initiated on the surface of porous silicon irradiated with laser radiation with wavelengths (λ = 266, 337, and 532 nm) in a wide range of intensities (up to 2 × 107W/cm2) were investigated. Laser-induced luminescence and laser mass-spectrometry were used as experimental procedures. X-ray reflection was used to determine the parameters of the porous silicon films. The photoluminescence spectra obtained at different wavelengths and low intensities were analyzed. This analysis showed that for an optically thin layer of porous silicon the luminescence spectrum does not depend on the wavelength of the exciting radiation. This indicates the existence of a separate system of levels in porous silicon that are responsible for the luminescence. The behavior of the photoluminescence spectra as a function of the intensity q of the exciting radiation was investigated. It was shown that the luminescence intensity is a nonlinear function of q. At high intensities of the exciting radiation, the luminescence intensity saturates and a short-wavelength shift of the spectra is observed; this is due to the high concentrations of photoexcited carriers. This increases the probability of the experimentally observed nonequilibrium photodesorption of H2 and Si from the surface of porous silicon. 相似文献
97.
S. P. Kuznetsov 《Journal of Experimental and Theoretical Physics》2008,106(2):380-387
A chaos generator consisting of two subsystems is considered. Each subsystem is a pair of parametrically coupled oscillators whose free-running frequencies differ by a factor of two. The subsystems are alternately driven by the third harmonic of a basic frequency, and energy is transferred between them through signal squarers. Based on a qualitative analysis and numerical results, a hypothesis is put forward that the system implements a hyperbolic strange attractor. 相似文献
98.
Theoretical expressions are obtained for the energy of spin waves in a layered antiferromagnetic structure (A type) of the perovskite-like compound LaMnO3. The Heisenberg exchange interactions of the central spin moment of the trivalent manganese ion (spin S = 2) with its eighteen neighbors from five coordination shells and the single-ion magnetic anisotropy energy are taken into account. The analysis is performed using six parameters: five exchange integrals and one anisotropy constant. Three of these five integrals determine the interactions in the two-dimensional ferromagnetic planes and two integrals characterize the interplanar interaction. The expressions derived for the magnon energy are valid for any direction and any magnitude of the quasi-momentum in the first Brillouin zone. For the three principal crystallographic directions, the theoretical results are compared with the experimental data for the dispersion curves obtained from inelastic neutron scattering studies of the LaMnO3 compound. It is shown that the in-plane ferromagnetic interaction can be more than sixteen times as great as the interplanar antiferromagnetic interaction. The conclusions drawn in this study are compared with the results obtained by other authors. 相似文献
99.
L. V. Chkhaidze T. D. Djobava L. L. Kharkhelauri E. N. Kladnitskaya A. A. Kuznetsov 《Physics of Atomic Nuclei》2004,67(4):693-702
Directed (in-plane) flows of protons, pions, and projectile light fragments (d, t, 3He, 4He) have been observed by investigating the dependence of the mean transverse momentum in the reaction plane 〈p x 〉 on the rapidity y in the c.m. system for CC collisions at a momentum of 4.2 GeV/c per nucleon. The comparison of our in-plane-flow results of protons with flow data for various projectile/target configurations was made using the scaled flow F s = F/(A P 1/3 + A T 1/3 ). F s demonstrates a common scaling behavior for flow values from different systems. From azimuthal distributions of protons and π? mesons, out-of-plane (squeeze-out) flow effects have been observed and the parameter a2 (the measure of the anisotropic emission strength) has been extracted. The quark-gluon string model reproduces the experimental results quite well. 相似文献
100.
We have investigated plasma turbulence at the edge of a tokamak plasma using data from electrostatic potential fluctuations measured in the Brazilian tokamak TCABR. Recurrence quantification analysis has been used to provide diagnostics of the deterministic content of the series. We have focused our analysis on the radial dependence of potential fluctuations and their characterization by recurrence-based diagnostics. Our main result is that the deterministic content of the experimental signals is most pronounced at the external part of the plasma column just before the plasma radius. Since the chaoticity of the signals follows the same trend, we have concluded that the electrostatic plasma turbulence at the tokamak plasma edge can be partially explained by means of a deterministic nonlinear system. 相似文献