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71.
Drutskoy A Abe K Abe K Abe T Aihara H Akatsu M Asano Y Aulchenko V Aushev T Bakich AM Ban Y Bay A Bedny I Behera PK Bizjak I Bondar A Bozek A Bracko M Browder TE Casey BC Chao Y Cheon BG Chistov R Choi Y Chuvikov A Danilov M Dash M Dong LY Eidelman S Eiges V Gabyshev N Garmash A Gershon T Golob B Haba J Hagner C Handa F Hastings NC Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hou WS Huang HC Igarashi Y Iijima T Inami K Ishikawa A Itoh R Iwasaki H Iwasaki M Iwasaki Y Jang HK Kang JH Kang JS 《Physical review letters》2004,92(5):051801
The radiative decay B-->phi K gamma is observed for the first time. The branching fraction for the charged B--->phi K- gamma decay mode is measured to be B(B--->phi K- gamma)=(3.4+/-0.9+/-0.4)x10(-6). The photon energy distribution for the B--->phi K- gamma decay is presented. The signal for the neutral B(0)-->phi K(0)gamma decay mode is not statistically significant and an upper limit, B(B(0)-->phi K(0)gamma)<8.3x10(-6) at 90% C.L., is set. The analysis is based on a data set of 90 fb(-1) collected by the Belle experiment at the e(+)e(-) asymmetric collider KEKB. 相似文献
72.
Fang F Hojo T Abe K Abe K Abe T Adachi I Aihara H Akatsu M Asano Y Aso T Aulchenko V Bakich AM Ban Y Banas E Bay A Behera PK Bizjak I Bondar A Bozek A Bracko M Brodzicka J Browder TE Casey BC Chang P Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Choi YK Danilov M Drutskoy A Eidelman S Eiges V Enari Y Fukunaga C Gabyshev N Garmash A Gershon T Golob B Hara T Hastings NC Hayashii H Hazumi M Heenan EM Higuchi T Hinz L Hokuue T Hoshi Y Hou WS Huang HC Igaki T Igarashi Y Iijima T Inami K 《Physical review letters》2003,90(7):071801
We report measurements of branching fractions for charged and neutral B-->eta(c)K decays where the eta(c) meson is reconstructed in the K(0)(S)K+/-pi(-/+), K+K-pi(0), K(*0)K-pi(+), and pp; decay channels. The neutral B0 channel is a CP eigenstate and can be used to measure the CP violation parameter sin(2phi(1). We also report the first observation of the B0-->eta(c)K(*0) mode. The results are based on an analysis of 29.1 fb(-1) of data collected by the Belle detector at KEKB. 相似文献
73.
A mean force exerted on a small rigid sphere by a sound wave in a viscous fluid is calculated. The force is expressed as a sum of drag force coming from the external steady flow existing in the absence of the sphere and contributions that are cross products of velocity and velocity derivatives of the incident field. Because of the drag force and an acoustic streaming generated near the sphere, the mean force does not coincide with the acoustic radiation pressure, i.e., the mean momentum flux carried by the sound field through any surface enclosing the sphere. If the sphere radius R is considerably smaller than the viscous wave penetration depth delta, the drag force can give the leading-order contribution (in powers of delta/R) to the mean force and the latter can then be directed against the radiation pressure. In another limit, delta< or =R, the drag force and acoustic streaming play a minor role, and the mean force reduces to the radiation pressure, which can be expressed through source strengths of the scattered sound field. The effect of viscosity can then be significant only if the incident wave is locally plane traveling. 相似文献
74.
B. A. Aronzon V. A. Kul’bachinskiĭ P. V. Gurin A. B. Davydov V. V. Ryl’kov A. B. Granovskiĭ O. V. Vikhrova Yu. A. Danilov B. N. Zvonkov Y. Horikoshi K. Onomitsu 《JETP Letters》2007,85(1):27-33
Magnetic and magnetotransport properties of GaAs(δ〈Mn〉)/In0.17Ga0.83As/GaAs quantum wells with different Mn concentrations are studied. The delta-doped manganese layer has been separated from the GaAs quantum well with a spacer with an optimal thickness (3 nm), which has provided a sufficiently high hole mobility (≥103 cm2V?1 s?1) in the quantum wells and their effective exchange with Mn atoms. It is found that the anomalous Hall effect (AHE) is exhibited only in a restricted temperature range above and below the Curie temperature, while the AHE is not observed in quantum wells with quasi-metallic conductivity. Thus, it is shown that the use of the AHE is inefficient in studying magnetic ordering in semiconductor systems with high-mobility carriers. The features observed in the behavior of the resistance, magnetoresistance, and Hall effect are discussed in terms of the interaction of holes with magnetic Mn ions with regard to fluctuations of their potential, hole transport on the percolation level, and hopping conduction. 相似文献
75.
L. V. Platonova P. S. Bednyakov S. A. Taraskin A. Yu. Danilov P. M. Pakhomov 《Moscow University Physics Bulletin》2011,66(2):169-173
Thin films of composite polymers based on polyvinylidenfluoride (PVDF), with ferroelectric fillers of No-Zr-Ti-Pb (NZTP-l)
were used to study the dielectric properties of the composites; specifically, we obtained the temperature dependence of the
dielectric permittivity at various frequencies at various contents of filler piezoceramic in the polymers. Measurements were
conducted using the bridge method and with the thermal noise method. In the studies with the bridge method, the range of the
frequencies was 25 Hz-1 MHz; in the studies with the thermal noise method, the frequencies varied from 1 to 100 kHz. 相似文献
76.
The principles of constructing optical devices on the basis of diffractive structures with a vanadium dioxide film for the
control of radiation in the mid-IR range are analyzed. Methods are described for the practical implementation of such devices
at λ=10.6 μm, and their response characteristics are calculated. It is shown that a contrast of 1:107 can be attained in diffractive optical elements, and the actuation time of the elements when switched on by an intense laser
beam can be shortened to tens of nanoseconds.
Zh. Tekh. Fiz. 69, 91–96 (November 1999) 相似文献
77.
Generalized solutions to the continuity equation in one-dimensional and multidimensional cases are constructed in the case of a discontinuous velocity field. 相似文献
78.
O. V. Vikhrova Yu. A. Danilov B. N. Zvonkov A. V. Kudrin V. V. Podol’skiĭ Yu. N. Drozdov M. V. Sapozhnikov C. Moura M. I. Vasilevskiy M. P. Temiryazeva 《Physics of the Solid State》2008,50(1):52-55
The InMnAs layers with ferromagnetic properties at room temperature are prepared by laser ablation. This is confirmed by the results of investigating the anomalous Hall and magneto-optical Kerr effects and by magnetic-force microscopy. According to x-ray diffraction data, the InMnAs layers have a fairly high crystal quality but contain inclusions of the MnAs hexagonal phase. An analysis of the electrical properties of the InMnAs layers suggests that the ferromagnetism revealed at room temperature cannot be accounted for by the presence of the MnAs phase but is associated with the charge carrier transfer in the InMnAs matrix. 相似文献
79.
We describe δ-shock wave generation from continuous initial data in the case of triangular conservation law system arising from “generalized pressureless gas dynamics model.” We use smooth approximations in the weak sense that are more general than small viscosity approximations. 相似文献
80.
I. M. Belousova V. A. Grigor’ev O. B. Danilov A. G. Kalintsev A. V. Kris’ko N. G. Mironova M. S. Yur’ev 《Optics and Spectroscopy》2001,90(2):292-301
A theoretical and experimental study of the contribution of light-induced scattering to nonlinear optical limitation is made. It is shown that light-induced scattering makes a considerable contribution to the optical limitation of radiation by fullerene-containing solutions. Radiation is scattered by small-scale (1–10 μm) inhomogeneities of density, and the corresponding increments are rather large. Because of this, scattering can be initiated by small-scale inhomogeneities of the input beam. Numerical simulation of nonlinear scattering is made, and the angular distribution and limitation of radiation in optical limiters are calculated. The calculation results are compared with the experiment. 相似文献