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951.
952.
QIAN Xian-Min Hon-Wah Tam 《理论物理通讯》2007,47(3):487-490
In this paper, we obtain a 1+1 dimensional integrable differential-difference model for the sine-Gordon equation by Hirota's discretization method. A bilinear Backlund transformation and the associated Lax pair are also proposed/or this model. 相似文献
953.
954.
C. Giusti F. D. Pacati M. Schwamb S. Boffi 《The European Physical Journal A - Hadrons and Nuclei》2007,33(1):29-38
Results for the cross-sections of the exclusive 16O(e, e'pn)14N and 16O(γ, pn)14N knockout reactions are presented and discussed in different kinematics. In comparison with earlier work, a complete treatment
of the center-of-mass (CM) effects in the nuclear one-body current is considered in connection with the problem of the lack
of orthogonality between initial bound and final scattering states. The effects due to CM and orthogonalization are investigated
in combination with different treatments of correlations in the two-nucleon overlap function and for different parametrizations
of the two-body currents. The CM effects lead in super-parallel kinematics to a dramatic increase of the 16O(e, e'pn) cross-section to the 12
+ excited state (3.95MeV) of 14N . In all the situations considered the results are very sensitive to the treatment of correlations. A crucial role is played
by tensor correlations, but also the contribution of long-range correlations is important. 相似文献
955.
N. A. Demekhina G. S. Karapetyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2007,42(6):215-222
The isomeric ratios of fragments of photofission of 238U and 232Th have been determined experimentally at the bremsstrahlung end-point of 50 and 3500 MeV. Results of measurements enabled us to estimate the mean angular momenta of primary fragments and to compare them with the published data. 相似文献
956.
E. Scalas U. Garibaldi S. Donadio 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,60(2):271-272
This erratum corrects a mistake in reference [E. Scalas, U. Garibaldi, S. Donadio, Eur. Phys. J. B 53, 267 (2006)].
In that paper,
we needed an aperiodic version of the BDY game, but, in formula (1),
we incorrectly presented
a periodic transition matrix of period 2 in the special case of g = 2 agents.
Here, we present the right aperiodic version. 相似文献
957.
A. A. Zakharenko 《Pramana》2007,69(4):617-629
In this work, the experimental results of the creation of the second non-dispersive Zakharenko wave (C
ph = C
g ≠ 0) in the negative roton branch (the so-called second sound) of the bulk elementary excitations (BEEs) energy spectra are
introduced. Several BEE signals detected by a bolometer situated in the isotopically pure liquid helium-II at low temperatures
∼100 mK are shown, which give evidence of negative roton creation in the liquid by helium atomic beams striking the liquid
surface. The negative roton signals were clearly distinguished by the following ways: the negative roton signal created by
helium atomic beams appeared earlier than the positive roton signal created by the beams, and presence of both positive and
negative roton signals together. It is natural that the negative roton creation by the beams requires the 4He-atom energies ∼12 K, while the positive roton creation by the atomic beams requires energies ∼35 K. Therefore, successive
increase in the heater power resulting in an increase in the 4He-atom energies gives solid evidence that the negative rotons are first created in the liquid by the helium atomic beams.
相似文献
958.
The effect of light noise on a Neurospora circadian clock system in the steady states is investigated. It is found that the circadian oscillations could be induced
by light noise, leading to various resonance phenomena including internal signal stochastic resonance (ISSR) and ISSR without
tuning in the system. The strength of ISSR could be significantly reinforced with the decrease of the distance of the control
parameter to the Hopf bifurcation point of the system. The fundamental frequency of noise-induced circadian oscillations almost
does not change with the increment of light noise intensity, which implies that the Neurospora system could sustain intrinsic circadian rhythms. In addition, the ISSR and ISSR without tuning could be both amplified,
suppressed or destroyed by tuning the frequency or amplitude of external signal. 相似文献
959.
B. Dybiec L. Schimansky-Geier 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(3):313-320
We study the stationary probability density of a Brownian particle in a potential with a single-well subject to the purely
additive thermal and dichotomous noise sources. We find situations where bimodality of stationary densities emerges due to
presence of dichotomous noise. The solutions are constructed using stochastic dynamics (Langevin equation) or by discretization
of the corresponding Fokker-Planck equations. We find that in models with both noises being additive the potential has to
grow faster than |x| in order to obtain bimodality. For potentials ∝|x| stationary solutions are always of the double exponential
form. 相似文献
960.
A.-J. Li C.-L. Wang L. Wang J.-H. Wu J.-Y. Gao 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,42(3):373-379
We investigate the spontaneously generated coherence (SGC) in a Doppler broadened four-level atomic system driven by two coherent
fields. We plot
the spontaneous emission spectra with different parameters and discuss how
the initial atomic conditions and parameters of both fields change the
number of peaks and dark lines of spontaneous emission spectra. Furthermore, we also show how the spontaneous emission spectrum
is modified by
Doppler effects in the viewed direction. Our results have important
references to the experimental observation of SGC in hot atomic vapors. 相似文献