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941.
The DELPHI Collaboration J. Abdallah et al. 《The European Physical Journal C - Particles and Fields》2003,27(2):153-172
A search for sleptons, neutralinos, charginos, sgoldstinos and heavy stable charged sleptons in the context of scenarios
where the lightest supersymmetric particle is the gravitino, is presented. Data collected during 2000 with the DELPHI detector
at centre-of-mass energies from 204 to 208 GeV were analysed and combined with all the data collected from 1995 to 1999 at
lower energies. No evidence for the production of sleptons, neutralinos and charginos has been found, therefore new limits
on the mass of these supersymmetric particles and on the model parameter space are set. The search for heavy stable charged
sleptons also updates the stable sleptons mass limit. The absence of evidence for sgoldstino production allows limits to be
set on its mass and on the scale of supersymmetry breaking.
Received: 6 November 2002 / Published online: 14 February 2003 相似文献
942.
B. Aneva 《The European Physical Journal C - Particles and Fields》2003,31(3):403-414
Deformed squeezed states are introduced as the q-analogues of the conventional undeformed harmonic oscillator algebra squeezed states. It is shown that the boundary vectors in the matrix-product states approach to multiparticle diffusion processes are deformed coherent or squeezed states of a deformed harmonic oscillator algebra. A deformed squeezed and coherent-states solution to the n-species stochastic diffusion boundary problem is proposed and studied.Received: 31 January 2003, Published online: 10 October 2003 相似文献
943.
We present a full treatment of the microcanonical ensemble of the ideal hadron-resonance gas starting from a quantum-mechanical formulation which is appropriate for the statistical model of hadronization. By using a suitable transition operator for hadronization we are able to recover the results of the statistical theory, particularly the expressions of the rates of different channels. Explicit formulae are obtained for the phase space volume or density of states of the ideal relativistic gas in quantum statistics as a cluster decomposition, generalizing previous ones in the literature. The problem of the computation of averages in the hadron gas microcanonical ensemble and the comparison with canonical ones will be the main subject of a forthcoming second paper.Received: 8 July 2003, Revised: 17 October 2003, Published online: 5 May 2004 相似文献
944.
The aim of this paper is to investigate homomorphisms which reserve square-free languages or primitive languages. A characterization of square-free-preserving homomorphisms is presented. We show that every square-free-preserving homomorphism is primitive-preserving. Strongly cube-free-preserving homomorphisms are also studied. 相似文献
945.
Pyroelectric effect in lead-magnoniobate-based solid solutions 总被引:1,自引:0,他引:1
E. P. Smirnova S. E. Aleksandrov K. A. Sotnikov A. A. Kapralov A. V. Sotnikov 《Physics of the Solid State》2003,45(7):1305-1309
A coordinated study of the dielectric, electrostriction, and pyroelectric properties of the lead-magnoniobate-based ceramic solid solutions 0.9PbMg1/3Nb2/3O3-0.1PbTiO3 and 0.55PbMg1/3Nb2/3O3-0.45PbSc1/2Nb1/2O3 conducted at the relaxor transition temperatures is reported. Electromechanical coupling stimulated by the giant electrostriction effect is shown to play an essential part in the pyroelectric effect. 相似文献
946.
947.
Hyperfine Interactions - In this paper, the conditions for which three-dimensional crystalline ion beams were attained in the rf quadrupole storage ring PALLAS at a velocity of around 2800 m/s are... 相似文献
948.
A method for suppressing self-modulation in backward-wave tubes is proposed. Additional delay is introduced into the feedback
circuit, owing to which the output signal amplitude affects the electron beam current that enters into the interaction space.
Numerical simulations demonstrate that the operating current in the single-frequency oscillation mode may be increased roughly
twofold. 相似文献
949.
Cao H. P. Chen G. Grechkoseeva M. A. Mazurov V. D. Shi W. J. Vasil'ev A. V. 《Siberian Mathematical Journal》2004,45(6):1031-1035
The spectrum of a finite group is the set of its element orders. A finite group G is said to be recognizable by spectrum, if every finite group with the same spectrum as G is isomorphic to G. The purpose of the paper is to prove that for every natural m the finite simple Chevalley group F
4(2
m
) is recognizable by spectrum. 相似文献
950.
H. Katsurada 《Journal of Number Theory》2004,104(1):100-117
We introduce a formula for the p-adic Siegel-Eisenstein series which demonstrates a connection with the genus theta series and the twisted Eisenstein series with level p. We then prove a generalization of Serre's formula in the elliptic modular case. 相似文献