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971.
On the possibility to create nonthermal solitions in a one dimensional magnetic sine-Gordon system I
The possibility to create nonthermal solitions by switching on an inhomogeneous magnetic field along the direction of a one dimensional magnetic chain is investigated using the inverse scattering method.Project of the Sonderforschungsbereich Frankfurt/Darmstadt, financed by special funds of the Deutsche Forschungsgemeinschaft 相似文献
972.
D. Ryter 《Zeitschrift für Physik B Condensed Matter》1981,41(1):39-42
Brownian motion in media with a space-dependent temperature and density is described by Langevin equations in phase space. Elimination of the velocity shows that diffusion inx-space cannot in general be characterized by a single diffusion parameter, nor can space-dependence always be accounted for by mere assignment of some sense of stochastic integration to the Langevin equation which has been reduced as in the homogeneous case. Steady solutions of the resulting equations agree with thermodynamics. Interactions between Brownian particles (giving rise to nonlinear Fokker-Planck equations) lead to a generalization of Einstein's relation.Work supported by the Swiss National Science Foundation 相似文献
973.
An expression is found for the first correction to the average field produced by a relativistic electron moving in a constant and homogeneous magnetic field. It has electric and magnetic components which do not depend on the time but have a complicated dependence on the distance to the direction axis of the magnetic field. The obtained expressions are analyzed as functions of the distance to the axis and also of the electron state.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 19–22, February, 1981.We thank Professor V. G. Bagrov for his interest in the work and valuable discussions of the results. 相似文献
974.
In the practical use of electron-beam discharge lasers an important problem is that of their operating reliability. The weakest spot of an EBL is the electron-gun partition foil, and the main cause of its failure is the breakdown of the discharge gap. This paper reports investigations of the mechanisms that destroy the foil and propose for its protection a method that makes it possible to significantly increase the operating reliability of the EBL.Translated from Trudy Ordena Lenina Fizicheskogo Institute Im. P. N. Lebedeva, Vol. 116, pp. 202–208, 1980. 相似文献
975.
Application of amorphous silicon field effect transistors in addressable liquid crystal display panels 总被引:1,自引:0,他引:1
A. J. Snell K. D. Mackenzie W. E. Spear P. G. LeComber A. J. Hughes 《Applied Physics A: Materials Science & Processing》1981,24(4):357-362
It is shown that thin-film field effect transistors (FETs) made from amorphous (a-) silicon deposited by the glow-discharge
technique have considerable potential as switching elements in addressable liquid crystal display panels. The fabrication
of the elements and their characteristics with steady and pulsed applied potentials are discussed in some detail. Two important
points are stressed: (i) a-Si device arrays can be produced by well-established photolithographic techniques, and (ii) satisfactory
operation at applied voltages below 15VV is possible. Small experimental 7×5 transistor panels have been investigated and
it is shown that with the present design up to 250-way multiplexing could be achieved. The reproducibility of FET characteristics
is good and in tests so far no change has been observed after more than 109 switching operations. 相似文献
976.
Resistivity and thermal conductivity of the intermediate valence compound CePd3 between 1.3 and 300 K are compared with those of the nonmagnetic and magnetic reference compounds YPd3 and GdPd3 and of alloys of the type Ce1–xRE
x
Pd3 with RE=Y, Gd and 0.01<x<0.5. The analysis reveals the existence of a maximum metallic resistivity of 300 cm for CePd3. The intrinsic resistivity of CePd3 rises proportional toT
2 up to 100 K, with a coefficientB about 107 times larger than e.g. in copper. We interpret this with indirect electron-electron scattering mediated through valence transitions. 相似文献
977.
DASP Collaboration R. Brandelik W. Braunschweig H. -U. Martyn H. G. Sander D. Schmitz W. Sturm W. Wallraff 《Physics letters. [Part B]》1979,80(4-5):412-418
Inclusive cross sections of η production by e+e- annihilation for c.m. energies between 4.0 and 5.0 GeV are presented. The η production is shown to be correlated with the production of a weakly decaying particle, indicating that its main source is F production. At the 4.42 GeV resonance it is correlated with a low energy photon, suggesting
or
production. A mass determination of the F is made at 4.42 GeV using the F → ηπ decay channel. 相似文献
978.
Ternary and quaternary fission produced in silver and bromine nuclei have been studied withK5 nuclear emulsion exposed to 1.8 GeV/cK
− beams. The frequency of the ternary events is found to be ∼0.08 of that of the binary events produced in the same volume
of the emulsion. The range ratio and range distribution of the fission fragments are studied and the angles between each pair
of the fragments are determined. Ranges are found to vary from 5 to 40μ with a maximum number lying between 5 and 10μ. The angles between the fission fragments are found to form a broad distribution extending from 40° to 180°. A few of the
events have also been analysed to give them a possible identity. A possible case of quaternary fission has also been reported.
This paper was presented at the Symposium on 3rd High Energy Physics held at Bhubaneswar during November 1976. 相似文献
979.
980.
Instantons and anti-instantons can profoundly influence the structure of a non-Abelian gauge theory involving N flavors of massless quarks. Interactions of the quarks with these pseudoparticles can spontaneously generate a quark mass, break the theory's SU(N) × SU(N) chiral symmetry and bind quark-antiquark pairs to form N2 ? 1 Goldstone bosons. If the spontaneously generated quark mass is small, multipseudoparticle configurations can be treated in a dilute gas approximation. 相似文献