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991.
H. G. Schuster 《Zeitschrift für Physik B Condensed Matter》1987,68(2-3):251-252
It is rigorously proved that for nonlinear dynamical systems whose time dependence is described by one dimensional, everywhere expanding maps, the width of broadband noise in the power spectrum is bounded by the generalized entropiesK
2 andK
3, which measure the strength of chaos in this system asK
22K
3.Dedicated to Professor Harry Thomas on the occasion of his 60th birthday 相似文献
992.
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
993.
The structures of the lightp-shell hypernuclei \({}_\Lambda ^6 He,{}_\Lambda ^7 Li,{}_\Lambda ^9 Liand{}_\Lambda ^9 Be\) are studied by using a realistic effectiveΛN interaction (YNG), and compared to those with the use of the simple one-range Gaussian (ORG) interaction. The YNG interaction, which simulates theΛNG-matrix for the Nijmegen OBE modelD, is characterized by the inner repulsive core and the density-dependence along with the space-exchange and spin-spin components. The framework we adopt is the microscopic α +x + Λ (x=n, d, t or α) three-cluster model, where nucleon antisymmetrization is exactly treated. The characteristic behaviors ofΛ?x andΛ?(αx) interactions derived from the YNG are displayed and discussed. In spite of the remarkable characteristic of YNG, the calculated energy levels of the four hypernuclei are very similar to those previous obtained by using the simple ORG interaction. The stabilization and contraction of the hypernuclear system due to the glue-like role ofΛ-particle persists in the present calculation, though the repulsive core of theΛN interaction tends to prevent from too much contraction. 相似文献
994.
W. Borchers R. Neugart E. W. Otten H. T. Duong G. Ulm K. Wendt ISOLDE Collaboration 《Hyperfine Interactions》1987,34(1-4):25-29
The hyperfine structure (hfs) and isotope shift (IS) in the isotopic chain of the radioactive element radon have been studied for the first time. The measurements were carried out by collinear fast-beam laser spectroscopy at the mass separator facility ISOLDE at CERN. The IS between 16 isotopes in the mass range 202A222 and the hfs of 7 odd-A isotopes were determined in the transitions 7s [3/2]2-7p [5/2]3 (745 nm) of Rn I. The nuclear spins and moments, as well as the observed inversion of the odd-even staggering for218–222Rn, can be associated with the effects of octupole instability around N=134.This work was supported by the Bundesministerium für Forschung und Technologie and the Deutsche Forschungsgemeinschaft. 相似文献
995.
J. Bendahán C. Broude E. Dafni G. Goldring M. Hass E. Naim M. H. Rafailovich 《Hyperfine Interactions》1987,34(1-4):139-142
The parity-violating mixing of the 17/2– and 17/2+ levels in93Tc nuclei, polarized by the tilted multifoil interaction, was measured by the observation of the forward-backward-ray asymmetry. The nuclear polarization, induced by the tilted multifoils, was measured directly for the neighboring88,90Zr isomers. The forward to backward asymmetry was determined to be A=(2.5±2.1) 10–3 which implies a parity violating matrix element ¦H
PV
)¦=(4.0±3.7)meV. 相似文献
996.
We have employed the TDPAC technique to measure the paramagnetic enhancement factor of140Ce in CeRh3B2 in the temperature range 300 K down to 115 K. Our measurements show that above Tc=115 K, the trend for(T) closely follows that for trivalent cerium. 相似文献
997.
M. Knopp K. -H. Speidel F. Hagelberg H. -J. Simonis J. Gerber P. N. Tandon 《Hyperfine Interactions》1987,34(1-4):183-186
A new method to detect polarization pick-up by ions emerging from thin polarized ferromagnetic layers has been tested. The applied technique consists in the observation of attenuated-angular correlations and atomic spin precessions for single-electron ions recoiling through vacuum in weak transverse magnetic fields. The Coulomb-excited19F(5/2+) state at 197 keV was used as probe. The experimental concept is described and the expected effects are discussed using the perturbed angular correlation formalism for polarized hyperfine interactions. 相似文献
998.
The temperature dependence of the electric quadrupole interaction frequency
l
o
, experienced by the181Ta probe occupying Hf site in the compounds Hf1-xTaxV2 has been measured for x=0.06, 0.10 and 0.20 in the temperature region between 8.5 K to 296 K. The measurements show lattice transformation in all the three compounds below 120 K. 相似文献
999.
G. R. Sudhakaran J. C. Sarker R. L. Bhattacharjee L. H. Johnston 《International Journal of Infrared and Millimeter Waves》1987,8(12):1531-1540
Submillimeter laser-Stark spectra have been observed for the isotopic species of methyl fluoride,13CH3F, using the 337 m line of the HCN laser. We have identified the multiplet transitions as JK=18K17K in the ground vibrational state. Ten distinct families with K=8, 9, 10, 11, 12, 13, 14, 15, 16 and 17 have been observed. Zero-field frequencies for all the transitions are given and in most cases with better accuracy than predicted from the previous constants. 相似文献
1000.
The Kirchhoff Matrix Tree Theorem provides an efficient algorithm for determiningt(G), the number of spanning trees of any graphG, in terms of a determinant. However for many special classes of graphs, one can avoid the evaluation of a determinant, as there are simple, explicit formulas that give the value oft(G). In this work we show that many of these formulas can be simply derived from known properties of Chebyshev polynomials. This is demonstrated for wheels, fans, ladders, Moebius ladders, and squares of cycles. The method is then used to derive a new spanning tree formula for the complete prismR n (m) =K m ×C n . It is shown that $$2^{\left( {\begin{array}{*{20}c} n \\ 2 \\ \end{array} } \right)\left( {1 - \frac{1}{{r - 1}} + o\left( 1 \right)} \right)} $$ whereT n (x) is then th order Chebyshev polynomial of the first kind. 相似文献