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931.
932.
Particle type dependences of hadron yield and emission patterns,
especially its difference between mesons and baryons, at intermediate
pT(2—5GeV/c) is one of the findings in heavy ion collisions at RHIC. A systematic study of identified hadron production was performed
in Au+Au/Cu+Cu collisions at sNN=62.4/200GeV, to investigate the possible origins of this difference. In this paper, we show particle ratios, elliptic flow strengths, and their scaling properties. 相似文献
933.
Temperature dependence of pressure broadening of the N = 1− fine structure oxygen line at 118.75 GHz
M.Yu. Tretyakov M.A. Koshelev I.A. Koval V.V. Parshin L.M. Kukin L.I. Fedoseev Yu.A. Dryagin A.F. Andriyanov 《Journal of Molecular Spectroscopy》2007,241(1):109-111
The absorption profile of the N = 1− fine structure line of oxygen was recorded by a resonator spectrometer at a frequency range of 110-130 GHz at atmospheric pressure and different temperatures ranging from −21 °C up to +22 °C. Analysis of the observed line shape allowed determination of the temperature dependence of the line pressure broadening. The measured value of the temperature exponent is n = 0.74(5) for self-broadening. Consistency of the measurements is supported by simultaneous measurements of the line intensity, the line mixing parameter and the line center frequency, and by comparison of obtained values with previously known data. 相似文献
934.
The transmission properties of one-dimensional photonic crystals containing double-negative and singlenegative materials are studied theoretically.A special kind of photonic band gap is found in this structure.This gap is invariant with scaling and insensitive to thickness fluctuation.But when changing the ratio of the thickness of two media.the width of the gap could be enlarged.The defect modes are analyzed by inducing a linear defect layer in the structure.It is found that the number of defect modes will increase when the thickness of the defect layer becomes larger. 相似文献
935.
FENG Shaotong HAN Dianrong & DING Heping Department of Physics Nanjing Normal University Nanjing China 《中国科学G辑(英文版)》2004,47(4):485-491
The extension of ordinary Fourier transform to the fractional Fourier transform (FRFT) was first accomplished by Namias in 1980. He gave a complete mathematical definition and discussed the eigenfunction of the transform. Using a system of lenses Lohmann et al.[1] first successfully realized the FRFT optically and designed the single lens mode and double lens mode for the realization of the FRFT of continuously variable fractional order. The concept of fractals was first proposed by Man… 相似文献
936.
R. Alicki M. Fannes B. Haegeman D. Vanpeteghem 《Journal of statistical physics》2003,113(3-4):549-574
This paper consists of two parts. First we set up a general scheme of local traps in a homogeneous deterministic quantum system. The current of particles caught by the trap is linked to the dynamical behaviour of the trap states. In this way, transport properties in a homogeneous system are related to spectral properties of a coherent dynamics. Next we apply the scheme to a system of Fermions in the one-particle approximation. We obtain in particular lower bounds for the dynamical entropy in terms of the current induced by the trap. 相似文献
937.
Klaus?FleischmannEmail author Vladimir?A.?Vatutin 《Journal of Theoretical Probability》2005,18(4):719-755
Consider a system of particles which move in Rd according to a symmetric α-stable motion, have a lifetime distribution of finite mean, and branch with an offspring law of index 1+β. In case of the critical dimension d=α/β the phenomenon of multi-scale clustering occurs. This is expressed in an fdd scaling limit theorem, where initially we start
with an increasing localized population or with an increasing homogeneous Poissonian population. The limit state is uniform,
but its intensity varies in line with the scaling index according to a continuous-state branching process of index 1+β. Our result generalizes the case α=2 of Brownian particles of Klenke (1998), where p.d.e. methods had been used which are not available in the present setting.
Supported in part by the DFG.
Supported in part by the grants RFBR 02-01-00266 and Russian Scientific School 1758.2003.1. 相似文献
938.
P. Cifuentes K. S. Kazarian A. San Antolí n 《Proceedings of the American Mathematical Society》2005,133(4):1013-1023
We characterize the scaling functions of a multiresolution analysis in a general context, where instead of the dyadic dilation one considers the dilation given by a fixed linear map such that and all (complex) eigenvalues of have absolute value greater than In the general case the conditions depend on the map We identify some maps for which the obtained condition is equivalent to the dyadic case, i.e., when is a diagonal matrix with all numbers in the diagonal equal to There are also easy examples of expanding maps for which the obtained condition is not compatible with the dyadic case. The complete characterization of the maps for which the obtained conditions are equivalent is out of the scope of the present note.
939.
For a linear autonomous difference equation with a unique real eigenvalue , it is shown that for every solution the ratio of and the eigensolution corresponding to is Cesàro summable to a limit which can be expressed in terms of the initial data. As a consequence, for most solutions the Lyapunov characteristic exponent is equal to . The proof is based on a Tauberian theorem for the Laplace transform.
940.
K.?V.?BerezinEmail author V.?V.?Nechaev P.?M.?él’kin 《Journal of Applied Spectroscopy》2005,72(1):9-19
The quartic force field of pyrazine has been calculated in the B3LYP/6-31G(d) hybrid density-functional approximation. Based on the results of this calculation, the total IR (250–3800 cm–1) and Raman (400–3200 cm–1) spectra of pyrazine have been interpreted with consideration for the Fermi and Darling-Dennison resonances and their spectral manifestations. A precision method is proposed for anharmonic analysis of the vibrational states of polyatomic molecules on the basis of consideration of their theoretical anharmonicity constants in combination with the corresponding experimental frequencies. The method of linear scaling of frequencies has been theoretically substantiated.__________Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 1, pp. 13–22, January–February, 2005. 相似文献