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181.
H. Jara K. Boyer U. Johann T. S. Luk I. A. McIntyre A. McPherson C. K. Rhodes 《Applied physics. B, Lasers and optics》1987,42(1):11-15
The results of transient loss measurements performed in a self-sustained discharge KrF* amplifier are reported. Analysis of these results gives a minimum value of 20 for the effective gain to loss ratiog
0/eff, indicating that efficient extraction of energy in subpicosecond KrF* amplifiers in the 1 J range should be achievable. 相似文献
182.
V. V. Ammosov A. G. Denisov G. S. Gapienko V. A. Gapienko V. I. Klyukhin V. I. Koreshev P. V. Pitukhin V. I. Sirotenko Z. U. Usubov V. G. Zaetz A. E. Asratyan A. V. Fedotov P. A. Goritchev S. P. Krutchinin M. A. Kubantsev I. V. Makhlueva V. I. Shekelyan V. G. Shevchenko A. B. Krebs 《Zeitschrift fur Physik C Particles and Fields》1987,36(3):377-381
The cross section of the quasi-elastic reactions \(\bar v_\mu p \to \mu ^ + \Lambda (\Sigma ^0 )\) in the energy range 5–100 GeV is determined from Fermilab 15′ bubble chamber antineutrino data. TheQ 2 analysis of quasi-elastic Λ events yieldsM A=1.0±0.3 GeV/c2 for the axial mass value. With zero µΛ K 0 events observed, the 90% confidence level upper limit \(\sigma (\bar v_\mu p \to \mu ^ + \Lambda {\rm K}^0 )< 2.0 \cdot 10^{ - 40} cm^2 \) is obtained. At the same time, we found that the cross section of reaction \(\bar v_\mu p \to \mu ^ + \Lambda {\rm K}^0 + m\pi ^0 \) is equal to \(\left( {3.9\begin{array}{*{20}c} { + 1.6} \\ { - 1.3} \\ \end{array} } \right) \cdot 10^{ - 40} cm^2 \) . 相似文献
183.
The critical exponents , and of undeuterated and partially deuterated ferroelectric betaine arsenate are estimated. Small but remarkable deviations from the tricritical values are observed. The obtained values are tested via scaling of the isothermals.At some distance aboveT
c a cross-over of the effective critical exponent to a value typically for short-range forces is observed. A suitably defined cross-over temperature range decreases with increasing deuteration and seems to vanish near the antiferroelectric phase boundary. 相似文献
184.
In the tree approximation, the critical relaxational dynamics of 2n with quenched random fields is calculated by renormalization near the upper critical dimensiond
u=4+2/(n–1). Although the relation between the characteristic frequency
c
q and the wave-numberq is as usual,unusual results are obtained for the asymptotic decay of the order-parameter correlation functionS(q,t).Dedicated to Prof. Dr. W. Döring on the occasion of his 75th birthday 相似文献
185.
U. Schotte 《Zeitschrift für Physik B Condensed Matter》1987,66(1):91-101
The hexagonal Jahn-Teller compounds ABCl3 (A=Cs, Rb; B=Cu, Cr) in their common high temperature phase are modeled as a system of independent elastic dipoles dressed by a far reaching strain field. The diffuse elastic cross section for neutrons is derived as for Huang scattering. Isointensity contours and line widths (FWHM) are calculated for CsCuCl3 and compared to experimental results, especially looking for correlations and precursor effects of the structural phase transition. 相似文献
186.
Summary Real hypersurfaces of an almost Hermitian manifold naturally admit an almost contact metric structure and the (f, g, u, v, w, , , )-structure is defined on submanifolds of codimension 3 of an almost Hermitian manifold. We study the so-called semi-invariant submanifolds of a complex space form with almost contact metric compound structure which is a general notion of (f, g, u, v, w, , , )-structure.Dedicated to professor Eulyong Pak on his 60th birthdayThis research was partially supported by Korean Science and Engineering Foundation Grant. 相似文献
187.
U. Stadtmüller 《Periodica Mathematica Hungarica》1986,17(2):83-108
We consider a class of nonparametric estimators for the regression functionm(t) in the model:y
i
=m(t
i
) +
i
, 1 i n, t
i
[0, 1], which are linear in the observationsy
i
. Several limit theorems concerning local and global stochastic and a.s. convergence and limit distributions are given. 相似文献
188.
H. Dijkstra R. Bailey E. Belau T. Böhringer M. Bosman V. Chabaud C. Damerell C. Daum G. de Rijk S. Gill A. Gillman R. Gilmore Z. Hajduk C. Hardwick W. Hoogland B. D. Hyams R. Klanner S. Kwan U. Kötz G. Lütjens G. Lutz J. Malos W. Männer E. Neugebauer H. Palka M. Pepé J. Richardson K. Rybicki H. J. Seebrunner U. Stierlin R. J. Tapper H. G. Tiecke M. Turala G. Waltermann S. Watts P. Weilhammer F. Wickens L. W. Wiggers A. Wylie T. Zeludziewicz ACCMOR Collaboration 《Zeitschrift fur Physik C Particles and Fields》1986,32(3):353-358
The joint production of ? mesons andπ ±,π 0,p, \(\bar p\) ,K s 0 andK ± is investigated using a sample of 600,000 inclusive ? meson events obtained in hadron Be interactions with incidentπ ±,p, \(\bar p\) andK ± beams. Evidence is presented for the joint production of ? mesons and strange particles produced with non-strange incident beams. With incidentK ± beam the number of additional strange particles is suppressed. The results are found to be in agreement with the qualitative predictions of a parton fusion model. The comparison with the Lund model for lowp T processes is fair. 相似文献
189.
In composite models of quarks, leptons and weak bosons whereW-constituents are colored objects, color octet partners ofW ± andZ 0 are predicted. We study in detail the phenomenology of these particles. Independent of the specific model one expects a color octet isotriplet of vector bosons (W 8 ± ,Z 8 0 ) with mass in the range of 100–200 GeV, and a color octet isosinglet vector bosonV 8 0 with substantially larger mass, due to mixing with the gluon. Moreover, relatively light color octet excitations of the leptons appear, while the existence of “color exotic” partners of the quarks is model dependent. These particles decay mainly into a lepton (quark) and a gluon. We construct the couplings ofW 8 ± ,Z 8 0 andV 8 0 to ordinary and “color exotic” fermions. The signals of color octet weak bosons in low energy weak reactions are explored in detail. The production cross section ofW 8 ± (Z 8 0 ) in hadron-hadron collisions is calculated for \(0.54TeV \leqq \sqrt s \leqq 20TeV\) . Various decay modes of colored weak bosons are studied. The most prominent decay signatures ofW 8 ± andZ 8 0 are events of the type (l +-: charged lepton;j: hadronic jet; : missing transverse momentum). The present CERN \(p\bar p\) collider data on such events are discussed in the light ofW 8 ± andZ 8 0 decays. If colored weak bosons are not found with a mass less than ~250 GeV composite model building will be strongly restricted. 相似文献
190.
The development of diffusion creep (DC) accompanying superplastic deformation (SPD) of the highly doped nickel alloy ZhS6KP is studied based on an investigation of the redistribution of dispersed intragrain deposits of the phase of Ni3(Al, Ti). Deposit-free zones (DFZ) are formed in the alloy, held at the temperature of SPD and accompanying deformation at the grain boundaries. The contribution of DC to the deformation was determined from a comparative analysis of the width of the DFZ in the deformed and undeformed parts of the samples for different grain sizes and rates of DC taking into account diffusion accommodation. It was established that for the optimum rate of SPD the upper limit of the contribution of DC to deformation for 2-m grains does not exceed 11%. It is concluded, based on the distribution of DFZ, that the effect of DC accompanying SPD is determined by diffusion fluxes, associated with the local concentration of stress accompanying the development of grain-boundary slipping.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 40–45, June, 1986.In conclusion, we thank Yu. M. Mishin for a useful discussion of the results. 相似文献