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121.
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
122.
G. D. Andreetti F. Ugozzoli A. G. Giumanini P. Traldi L. Lassiani A. Varnavas 《Journal of chemical crystallography》1991,21(6):721-728
The decomposition of the gaseous positive ions of the title compounds obtained by electron impact have been completely mapped. The X-ray structural determinations of these two substances established their identity definitively and allowed to reveal some interesting features of these molecules of pharmaceutical interest. 相似文献
123.
V. F. Babenko 《Ukrainian Mathematical Journal》1991,43(9):1064-1076
We compute Kolmogorov widths in the space L1 for classes of periodic functions representable in the form of a kernel convolution that does not increase the number of sign changes with values in a given transposition invariant set of functions, and solve the optimization problem for quadrature formulas in these classes.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 43, No. 9, pp. 1135–1148, September, 1991. 相似文献
124.
N. M. Agababyan M. R. Atayan M. Charlet J. Czyżewski E. A. De Wolf K. Dziunikowska A. M. F. Endler Z. Sh. Garutchava H. R. Gulkanyan R. Sh. Hakobyan J. K. Karamyan D. Kisielewska W. Kittel S. S. Mehrabyan Z. V. Metreveli E. C. Oliveira K. Olkiewicz F. K. Rizatdinova E. K. Shabalina L. N. Smirnova M. D. Tabidze L. A. Tikhonova A. V. Tkabladze A. G. Tomaradze F. Verbeure S. A. Zotkin 《Zeitschrift fur Physik C Particles and Fields》1996,71(1):405-414
The NA22 data onπ ? π ? correlations are analyzed in terms of a number of two- and three-dimensional parametrizations (Gaussian space-time, Goldhaber, Bowler string-like, Bertsch hydrodynamical, Kopylov-Podgoretskii, etc.). Contrary to the results obtained for e+e? andµp collisions, the Goldhaber parametrization, as well as string-like models, fail in describing the hadron-hadron data. Better fits are obtained in the framework of surface-emitting fireball-like models, both when including and excluding hydrodynamical expansion of nuclear matter. Our results indicate that pion radiation occurs at earlier stages of matter evolution than in nuclear collisions. 相似文献
125.
An investigation was made of the resonance conditions in systems of one-dimensional potential barriers of a general kind. The types of systems are identified and the conditions determined which are necessary for observing a broad resonance in which the first three derivatives of the energy transmission coefficient are equal to zero. The conditions are found for observing an isolated resonance with complete transparency on a background of resonances with incomplete transparency.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 49–53, August, 1993. 相似文献
126.
V. F. Balakirev S. Kh. Estemirova A. M. Yankin S. G. Titova 《Doklady Physical Chemistry》2007,416(1):240-242
127.
Magnetic-field-induced polymorphism of biperiodic stripe domain structures of films with a positive anisotropy constant and
easy axis parallel to the normal to the surface is studied. A symmetry classification of the observed types of domain structures
is performed, and the phase diagram of the films in the (H
⊥, H
∥) plane, where H
⊥ and H
∥ are, respectively, the components of the magnetic field vector perpendicular and parallel to the normal to the surface, is
determined.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 9, 701–706 (10 May 1998) 相似文献
128.
Yu. G. Abov D. S. Denisov N. O. Elyutin S. K. Matveev Yu. I. Smirnov A. O. Éidlin F. S. Dzheparov D. V. L’vov 《Journal of Experimental and Theoretical Physics》1998,87(6):1195-1200
The asymptotic behavior of the spectra for large values of the scattering vector for the case of elastic multiple small-angle
neutron scattering (SANS) is investigated theoretically and experimentally. An expansion of the spectrum in terms of the reciprocal
of the magnitude of the momentum transfer is obtained taking account of the influence of the instrumental line. It is shown
that, to within some factor, the leading term of the expansion is identical to the differential single-scattering cross section
averaged over a statistical ensemble of particles; several subsequent terms in the expansion are calculated and the range
of applicability of the resulting expressions is determined. The asymptotic behavior of the multiple SANS spectrum is measured,
using a two-crystal neutron spectrometer, for samples of an HTSC ceramic, the alloy Fe-Ni, and Al powder. The agreement between
the experimental results and the theoretical predictions is analyzed.
Zh. éksp. Teor. Fiz. 114, 2194–2203 (December 1998) 相似文献
129.
R. F. Bilyalov 《Russian Physics Journal》1998,41(11):1134-1138
A covariant spinor derivative is constructed in arbitrary reference frames and also in coordinates, with specified arbitrary
linear connectedness.
Kazan State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 78–83, November, 1998. 相似文献
130.
D. F. Kurdgelaidze 《Russian Physics Journal》1998,41(10):1042-1050
On the basis of nonassociative spinor field theory, the specific properties of a nonassociative spinor field are investigated.
A new quantum number is introduced: the associator, which is a measure of the nonassociativeness of the field. To calculate
the associator and spin in nonassociative algebra, open and closed products are introduced. It is shown that the spin consists
of two components: the first half (calculated by the open-product rule) is similar to ordinary spin, while the second half
(calculated by the closed-product rule) is attributed to the associator, i.e., is related to shear in the auxiliary isotopic
space. The associator basis is expanded to a complete octonion basis, and the Poincaré group of four-dimensional space is
expanded to a Poincaré group of eight-dimensional space. It is shown that, from these generators, in the particle rest system,
the nonzero independent eigenvalues are: one, the sign of the particle energy, one of the spin components, one of the associator
spatial components, and c7.
Tbilisi Medical Institute. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 101–109, October, 1998. 相似文献