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141.
V. N. Vasil’ev S. A. Kozlov P. A. Petroshenko N. N. Rozanov 《Optics and Spectroscopy》2004,96(2):182-186
The nonparaxial dynamics of spectra of pulses comprising a few cycles of a light field is analyzed in transparent nonlinear media with dispersion. It is shown that the inhomogeneous self-broadening of the time spectrum of a pulse proceeds more effectively into the blue region at all spatial frequencies. A decrease in the energy in the central part of the time spectrum is realized mainly at high spatial frequencies. 相似文献
142.
143.
Annihilation of positrons in hydrogen-saturated titanium 总被引:1,自引:0,他引:1
K. P. Aref’ev O. V. Boev O. N. Imas A. M. Lider A. S. Surkov I. P. Chernov 《Physics of the Solid State》2003,45(1):1-5
The effect of atomic hydrogen on the electronic structure of α-titanium samples is studied using the electron-positron annihilation methods. It is shown that different states of hydrogen atoms are manifested in different ways in the positron lifetime distribution spectrum. The results of theoretical calculations of the first component of the positron lifetime are in accord with the obtained experimental data. 相似文献
144.
A microscopic theory of the Efetov supermatrix sigma-model type is constructed for the low-lying electron states in a mixed
superconductive-normal system with disorder. This technique is used for the study of the localized states in the core of a
vortex in a moderately clean superconductor with τ
−1≫ω
0∼Δ2/E
F
. At low energies ε≪ω
Th∼ (ω
0/τ)1/2, the energy level statistics is described by the “zero-dimensional” limit of this supermatrix theory, and the result for
the density of states is equivalent to that obtained within Altland-Zirnbauer random matrix model. Nonzero modes of the sigma
model increase the mean interlevel distance by the relative amount [2 ln (1/ω
0
τ)]−1.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 1, 78–83 (10 July 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
145.
Time-resolved pulsed spectroscopy was used to measure the luminescence spectra of calcium fluoride. Characteristic features
of the luminescence of self-trapped excitons are discussed. It is shown that various configurations of self-trapped excitons
incorporating hole nuclei of a more complex structure, may be formed in CaF2 crystals.
Fiz. Tverd. Tela (St. Petersburg) 40, 1226–1227 (July 1998) 相似文献
146.
A. S. Mart’yanov 《Mathematical Notes》2007,82(1-2):57-66
In this paper, we study a dynamic reconstruction algorithm which reconstructs the unknown unbounded input and all unobservable phase coordinates from the results of measurements of part of the coordinates. An upper and a lower bound for the accuracy of the reconstruction is obtained. We determine the class of inputs for which the upper bound is uniform. We give a condition for optimally matching the algorithm parameters, ensuring the highest order of the upper bound and equating the orders of the upper and lower bounds. Thus, we establish the sharpness of the upper bound. 相似文献
147.
V. N. Korneev P. M. Sergienko V. A. Shlektarev V. M. Aul’chenko M. A. Bukin V. M. Titov B. P. Tolochko M. R. Sharafutdinov A. V. Zabelin E. I. Litvinov A. M. Matyushin V. G. Stankevich M. A. Sheromov O. V. Naida A. A. Vazina 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2007,1(1):99-104
To modernize the DICSI station, new hardware and software have been created according to the conditions of the operating storage ring “Sibir’-2” beam channel. The recording system has been successfully tested on the operating channel of the storage ring VEPP-3 (Budker Institute of Nuclear Physics Siberian Branch, Russian Academy of Sciences, Novosibirsk) using the time-resolved “diffraction cinema” technique in studying real biological objects in the static and dynamic modes of data accumulation. At the DICSI station, structural changes in medical and biological objects are permanently investigated. The specific structure dimensions of these objects are in the nanometric range. 相似文献
148.
The 2-meter liquid-hydrogen bubble chamber is exposed to a separated beam of α particles from the ITEP synchrotron. The momentum of the incident 4He nuclei, averaged over the fiducial volume of the chamber, is 5 GeV/c (the kinetic energy of initial protons in the nucleus rest frame is T
p
=620 MeV). The spectral functions of decays α→tp and α→τn) are extracted in the 4π geometry (the latter is extracted for the first time) from the exclusive reactions αp→tpp and αp→τpn in the spectator momentum region 0<q<0.3 GeV/c. The pole dominance criteria are carefully checked. Extrapolation of the nuclear vertex function to the pole gives a lower
bound on the nuclear vertex constant. Our experimental data are compared with the results of other studies and with theoretical
calculations.
Pis’ma Zh. éksp. Teor. Fiz. 66, No. 2, 69–74 (25 July 1997)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
149.
150.