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991.
992.
R. L. Dobrushin A. Pellegrinotti Yu. M. Suhov L. Triolo 《Journal of statistical physics》1988,52(1-2):423-439
The long-time behavior of an infinite chain of coupled harmonic oscillators is studied. In addition to a limiting hydrodynamic (Euler-type) equation, the next approximation is investigated. The corresponding equation is derived. 相似文献
993.
By applying magnetic fields up to 2 kG, the equation of state and the critical dynamics of a spin system near its critical point can be studied with the Mössbauer effect. As an example, the equation of state near the Curie temperature of iron is investigated yielding the critical exponent =4.84±0.15. 相似文献
994.
Z. M. Stadnik P. Griesbach P. Gütlich G. Stroink T. Kohara 《Hyperfine Interactions》1988,41(1):705-708
61Ni Mössbauer measurements have been performed at 4.2 K on spherical Ni particles with an average diameter of 100 and 30 Å, covered with a protective layer of SiO. Their spectra contain a surface component with a significantly reduced hyperfine magnetic field as compared with the field in the bulk. This result confirms recent theoretical predictions. 相似文献
995.
Results are presented on the operation and optimization of soliton Raman fibre-ring lasers using a c.w. mode-locked Nd-YAG laser at 1.32m as the source of 100 ps pump pulses. Various lengths of standard single-mode silica fibre were used, and tunable pulses as short as 100 fs generated.On leave from Departamento de Fisica, Universidade Federal de Alagoas, Maceio, 57000-AL, Brazil 相似文献
996.
Dupieux P Alard JP Augerat J Babinet R Bastid N Brochard F Charmensat P De Marco N Fanet H Fodor Z Fraysse L Girard J Gorodetzky P Gosset J Laspalles C Lemaire MC L'Hôte D Lucas B Marroncle J Montarou G Parizet MJ Poitou J Qassoud D Racca C Schimmerling W 《Physics letters. [Part B]》1988,200(1-2):17-21
Proton-proton small angle correlations have been measured in neon-nucleus collisions, using the 4 pi detector Diogene, at 400 and 800 MeV per nucleon incident energies. Values of the size of the emitting region are obtained by comparison with the Koonin formula, taking into account the biases of the apparatus. The dependence of the density on target mass and incident energy is also analysed. 相似文献
997.
A. Vanelstraete C. Laermans L. Lejarraga M. von Schickfus S. Hunklinger 《Zeitschrift für Physik B Condensed Matter》1988,70(1):19-23
The internal friction of two neutron-irradiated quartz samples was measured at audio-frequency as a function of temperature. This is an extension of acoustic measurements to much lower frequencies and thus to much longer time scales. A temperature independent behaviour has been observed and is discussed in the framework of the tunnelling model. One of the major assumptions of this model regarding the tunnelling states with long relaxation time could be verified for neutron-irradiated quartz. 相似文献
998.
H. Arenhövel W. Leidemann E. L. Tomusiak 《Zeitschrift für Physik A Hadrons and Nuclei》1988,331(2):123-138
The influence of the neutron electric form factor on various observables in two-body break-up of deuterons by electrons such as differential cross section, beam, target and beam-target asymmetries and outgoing nucleon polarization as well is investigated for different kinematic regions. The electron-deuteron vector asymmetryA ed V and the outgoing nucleon polarization component P′x(n) are the most promising observables in and off the quasi-free region for a determination ofG En. Also the single polarization observablesA d T and Py 0(p) and the double polarization observable P′z(n) show significant influences fromG En. 相似文献
999.
M. A. Alberg E. M. Henley L. Wilets 《Zeitschrift für Physik A Hadrons and Nuclei》1988,331(2):207-210
A new quark model forN \(\bar N\) annihilation is proposed. It is argued that a linear superposition of the so-called3P0 and3S1 models is more consistent with QCD and the inclusion of quark degrees of freedom inNN scattering, and is also suggested by the data. A comparison is made, in Born approximation, with the angular distribution for \(p\bar p \to \Lambda \bar \Lambda \) . 相似文献
1000.
L. Käubler W. Enghardt H. Prade P. Carlé L. O. Norlin K. -G. Rensfelt U. Rosengård 《Zeitschrift für Physik A Hadrons and Nuclei》1988,329(2):143-150
Using the reaction138Ba(α,2n)140Ce the magnetic moment of the 10 1 + isomer atE x =3714.7 keV in theN=82 nucleus140Ce has been determined by means of the TDPAD method toμ=+10.3(4)μ N . Measuredg-factors in140Ce are compared to calculations within the shell model with configuration mixing. For the 10 1 + isomer in140Ce the four proton configuration π(1g 7 2/2 ,2d 5 2/2 ) has been found to be dominant. From theg-factor measurement strong contributions of multiparticle excitations to thegp2d 3/2,π3s 1 2 or π1h 11 2 shells and admixtures of neutron excitations to the wave function of the 10 1 + state could be excluded. The strongE1γ-branch of the deexcitation of the 10 1 + isomer in140Ce can be explained by means of small admixtures of configurations which contain the outer subshell excitationsπ2f 7/2 andπ1h 9/2. On this basisE1 transitions experimentally observed in theN=82 nuclei140Ce,141Pr and145Eu may be understood. 相似文献