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991.
V.L. Alexeev B.A. Emelianov L.P. Kabina D.M. Kaminker Yu.L. Khazov I.A. Kondurov E.K. Leushkin Yu.E. Loginov V.L. Rumjantsev S.L. Sakharov A.I. Smirnov P.A. Sushkov 《Nuclear Physics A》1975,248(2):249-275
Low-energy γ-ray and conversion electron spectra from the 133Cs(n,γ)134Cs reaction have been investigated with a bent cyrstal spectrometer, β-speetrometer, Ge(Li) and Si(Li) detectors. Gamma-gamma coincidence measurements were made with the Ge(Li)-Ge(Li) arrangement. Gamma-gamma delayed coincidences have been studied with the use of the Ge(Li)-NaI(Tl) coincidence set-up. The decay of 2.9 h 134mCs has been investigated with the prism β-spectrometer and Ge(Li) detector. The half-lives of the 176.403 and 257.112 keV levels have been measured to be 49.7 ± 0.8ns and 12.3 ± 1.1 ns respectively. The neutron binding energy Bn have been calculated to be 6891.4 ± 1.3 keV. Spin and parity assignments have been made for almost all the levels. The possible structure of the levels deduced is discussed. 相似文献
992.
993.
A. A. Petrov und Ju. S. Smirnov 《Colloid and polymer science》1977,255(8):815
Ohne Zusammenfassung 相似文献
994.
995.
L. S. Smirnov A. I. Baranov L. A. Shuvalov L. Bobrowicz-Sarga I. Natkaniec S. Waplak 《Physics of the Solid State》2001,43(1):117-126
The (NH4)3H(SO4)2 and [(NH4)0.82Rb0.18]3H(SO4)2 crystals are investigated by dielectric spectroscopy, inelastic incoherent neutron scattering (IINS), and neutron powder diffraction. A comparative analysis of the data obtained is given. It is shown that the phase transitions II ? III, III ? IV, IV ? V, and V ? VII in the (NH4)3H(SO4)2 crystal are accompanied by changes in the orientation ordering of the NH 4 + ions. In the [(NH4)0.82Rb0.18]3H(SO4)2 crystal, these phase transitions are completely suppressed and the long-range order inherent in the II phase is retained over the entire temperature range covered (6–300 K). It is revealed that this crystal at the temperature T g≈70 K undergoes a transition to the dipole glass phase, which is attended by “freezing” the orientation disordering of the ammonium ions. 相似文献
996.
Yu. M. Smirnov 《Optics and Spectroscopy》2004,97(5):677-682
The excitation of the singlet S and P° levels of a Sr atom from the ground state by slow electrons was studied by the method of extended crossing beams. It was ascertained that perturbations manifest themselves in the behavior of the excitation cross sections in the spectral series arising as a result of the transitions from these levels. The perturbations affect to a larger extent the form of the optical excitation functions rather than the absolute values of the cross sections. The results obtained are compared with previous data. 相似文献
997.
We have solved the evolution equation for neutrinos in a low density medium, Vnu(e), we have found the attenuation effect: a decrease of the sensitivity to remote structures, d>l(nu)E/DeltaE, where l(nu) is the oscillation length and DeltaE/E is the energy resolution of a detector. 相似文献
998.
Ray in a waveguide can be considered as a trajectory of the corresponding Hamiltonian system, which appears to be chaotic in a nonuniform environment. From the experimental and practical viewpoints, the ray travel time is an important characteristic that, in some way, involves an information about the waveguide condition. It is shown that the ray travel time as a function of the initial momentum and propagation range in the unperturbed waveguide displays a scaling law. Some properties of the ray travel time predicted by this law still persist in periodically nonuniform waveguides with chaotic ray trajectories. As examples we consider few models with special attention to the underwater acoustic waveguide. It is demonstrated for a deep ocean propagation model that even under conditions of ray chaos the ray travel time is determined, to a considerable extent, by the coordinates of the ray endpoints and the number of turning points, i.e., by a topology of the ray path. We show how the closeness of travel times for rays with equal numbers of turning points reveals itself in ray travel time dependencies on the starting momentum and on the depth of the observation point. It has been shown that the same effect is associated with the appearance of the gap between travel times of chaotic and regular rays. The manifestation of the stickiness (the presence of such parts in a chaotic trajectory where the latter exhibits an almost regular behavior) in ray travel times is discussed. (c) 2002 American Institute of Physics. 相似文献
999.
I. V. Ajinenko S. A. Akimenko G. A. Akopdzhanov K. S. Belous G. I. Britvich I. G. Britvich A. P. Filin V. N. Govorun A. V. Inyakin V. A. Khmelnikov A. S. Konstantinov V. F. Konstantinov I. Ya. Korolkov V. M. Leontiev V. P. Novikov V. F. Obraztsov V. A. Polyakov V. I. Romanovsky V. M. Ronjin V. A. Senko N. A. Shalanda M. M. Shapkin V. I. Shelikhov N. E. Smirnov A. A. Sokolov O. G. Tchikilev E. V. Vlasov O. P. Yushchenko V. N. Bolotov S. V. Laptev A. Yu. Polyarush V. E. Postoev S. V. Yashchenko B. Zh. Zalikhanov V. Z. Serdyuk 《Physics of Atomic Nuclei》2002,65(11):2064-2069
The decay K ? → e ? νπ 0 has been studied using in-flight decays detected with the ISTRA+ setup working at the 25-GeV negative secondary beam of the U-70 PS. About 130K events were used for the analysis. The λ + parameter of the vector form factor has been measured: λ +=0.0293±0.0015(stat.)±0.002(syst.). The limits on the possible tensor and scalar couplings have been derived: f T/f +(0)=?0.045±0.060(stat.) and f S/f +(0)=?0.019 ?0.016 +0.025 (stat.). 相似文献
1000.
A. E. Sovestnov V. A. Shaburov Yu. P. Smirnov A. V. Tyunis A. V. Golubkov 《Physics of the Solid State》2002,44(8):1570-1573
For Sm1?x R x S (R=Ce, Gd, Y) systems with intermediate valence, the population of Sm 4f states (valence) and populations of Ce 5d, Gd 5d, and Y 4d states are determined by the method of x-ray line displacement. It is found that, in all the systems under investigation, the valence of Sm upon transition to the intermediate valence state increases from m≈2.5 (x≈0.15–0.25) to m≈2.65 (x≈0.8) and then decreases. The populations of Ce, Gd, and Y d states remain nearly constant over the entire region of compositions: $\bar n_d = 0.78 \pm 0.03,0.43 \pm 0.04$ , and 1.07±0.04 for Ce, Gd, and Y, respectively. The experimental dependence of the Sm valence on the composition is explained under the assumption that the 4f electron of an Sm atom can be hybridized through two channels, namely, with the 5d electron of the neighboring Sm atom and with its own 5d electron. 相似文献