Hydrogen passivation of vacancy-related centres in silicon

IR studies of interactions of atomic hydrogen with the A- and E-centres in silicon are performed. The MINDO/3 calculations of electronic structures and elastic constants of the hydrogen-related centres are also presented.     

Radar observations of artificial ionospheric turbulence during a magnetic storm

We present the results of radar observations of artificial ionospheric turbulence (AIT) created due to modification of the ionosphere by high-power radio emission from the Sura heating facility (Nizhny Novgorod region, Russia). Measurements were carried out in August 18–22, 2003 in the evening time (16:00–20:00 UT) with the use of over-the-horizon chirp HF radars on the Khabarovsk-Rostov-on-Don, Irkutsk-Rostov-on-Don, Inskip (England)-Rostov-on-Don paths, and also on the Moscow-Rostov-on-Don path for which reference signals of the standard-time RVM station were received. It is found that conditions for propagation of HF signals through the upper ionosphere at frequencies exceeding the maximum usable frequency for standard hop propagation through the F region were realized on the Irkutsk-Sura path in the presence of the powerful sporadic E_s layer. The presence of such signals was revealed at the Rostov-on-Don station by receiving radio waves which escape from the altitudes of the ionospheric F region due to scattering by artificial small-scale magnetic-field-aligned irregularities. We studied the ionospheric effects of a magnetic storm occurring during the experiment by using the measurement data of the Doppler frequency shift of signals scattered by artificial ionospheric turbulence. It is shown that during a magnetic storm, the electric field and the drift velocity of irregularities at the altitudes of the F layer over the Sura facility reach values of 8.6 mV/m and 186 m/s, respectively, which are typical of the high-latitude ionosphere. We consider the relation between quasi-periodic oscillations of the Doppler frequency shift of the scattered signal and propagation of magnetohydrodynamic waves excited during the magnetospheric storm.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 47, No. 9, pp. 722–738, September, 2004.     

Interferometry of direct photons in central 208Pb + 208Pb collisions at 158A GeV

Two-particle correlations of direct photons were measured in central 208Pb+208Pb collisions at 158A GeV. The invariant interferometric radii were extracted for 100相似文献   

Destruction of silica fiber cladding by the fuse effect

The phenomenon of destruction of silica fiber cladding by the fiber fuse effect has been observed for the first time to the authors' knowledge. Experiments on the optical discharge propagation along a fiber were conducted with fibers of decreased cladding thickness. The destruction of fiber cladding led to expansion of the optical discharge plasma and to a decrease of its density. This resulted in the termination of optical discharge propagation. The section of a fiber with decreased cladding thickness can act as a safety device to halt damage propagation.     

On probabilities of moderate deviations of sums for independent random variables

We investigate asymptotics of probabilities of moderate deviations and their logarithms for an array of row-wise independent random variables with finite variations and finite one-sided moments of order p > 2. The range of the zone of normal convergence is calculated in terms of Lyapunov ratios constructed from the positive parts of the random variables. Bounds for probabilities of moderate deviations are also derived in the case where the normal convergence fails. Bibliography: 16 titles.Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 294, 2002, pp. 200–215.This research was partially supported by the Russian Foundation for Basic Research, grant 02-01-00779, and by the Program Leading Scientific Schools, grant 00-15-96019.Translated by A. N. Frolov.     

First measurement of the transverse spin asymmetries of the deuteron in semi-inclusive deep inelastic scattering

First measurements of the Collins and Sivers asymmetries of charged hadrons produced in deep-inelastic scattering of muons on a transversely polarized 6LiD target are presented. The data were taken in 2002 with the COMPASS spectrometer using the muon beam of the CERN SPS at 160 GeV/c. The Collins asymmetry turns out to be compatible with zero, as does the measured Sivers asymmetry within the present statistical errors.     

Asymptotic Behavior of Increments of Sums over Monotone Blocks

We investigate the almost sure asymptotic behavior of increments of sums of i.i.d. random variables over increasing runs in an associate sequence. The Shepp law, the Erds–Rényi law, and the Csörg–Révéesz law are obtained for increments of sums over increasing runs formed by random variables taking their values in a fixed interval. Bibliography: 17 titles.     

On Asymptotics of Large Increments of Sums in Non-i.i.d. Case

The almost sure asymptotic behavior of large increments of partial sums is investigated in case of independent nonidentically distributed random variables. One-sided variants of the Csörg–Révész strong approximation laws are obtained in non-i.i.d. case.