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1.
Although the structure of a glass closely resembles that of a dense liquid over short length scales, its solidity implies that the two-particle distribution function is long range. In this paper the explicit form of this long range behaviour is derived in terms of the elastic constants of the glass and the relationship is shown between density fluctuations and the microscopic form of the displacement vector u(r). With minor modifications these results are valid also for a crystal. Several ramifications of these results are explored.  相似文献   

2.
Nuclear collision experiments exhibit correlations peaked in relative azimuthal angle with a long range in rapidity. Called the ridge, this peak occurs both with and without a jet trigger. We argue that the energy and projectile-mass dependence of the ridge can be described by an early Glasma stage followed by hydrodynamic flow.  相似文献   

3.
4.
T. Lappi  L. McLerran 《Nuclear Physics A》2010,832(3-4):330-345
We analyze long range rapidity correlations observed in the STAR experiment at RHIC. Our goal is to extract properties of the two particle correlation matrix, accounting for the analysis method of the STAR experiment. We find a surprisingly large correlation strength for central collisions of gold nuclei at highest RHIC energies. We argue that such correlations cannot be the result of impact parameter fluctuations.  相似文献   

5.
We calculate long range multiplicity correlations ine + e ? annihilation. Perturbative, probabilistic models predict vanishing multiplicity correlations between two opposite jets, in contrast to the results for non-perturbative models. The former still lead to strong long range correlations within one jet.  相似文献   

6.
Recent analyses of fluctuations in non-equilibrium systems by Prigogine, Malek-Mansour and Nicolis have indicated the existence of a minimal coherence length beyond which fluctuations can amplify and induce instabilities at a macroscopic scale. Conversely, this observation suggests the emergence of long range spatial correlations in systems undergoing non-equilibrium unstable transitions. In the present paper, this problem is analyzed for reaction-diffusion systems and illustrated on a specific model. The existence of diverging form factors and of long range correlations is established. The connection between the multi-variate master equation and the local equation developed recently by Prigogine, Malek-Mansour and Nicolis is discussed.  相似文献   

7.
We study the RHIC data on long range rapidity correlations, comparing their main trends with different string model simulations. Particular attention is paid to color percolation model and its similarities with color glass condensate. As both approaches corresponds, at high density, to a similar physical picture, both of them give rise to a similar behavior on the energy and the centrality of the main observables. Color percolation explains the transition from low density to high density.  相似文献   

8.
We address the relation between long-range correlations and charge transfer efficiency in aperiodic artificial or genomic DNA sequences. Coherent charge transfer through the highest occupied molecular orbital states of the guanine nucleotide is studied using the transmission approach, and the focus is on how the sequence-dependent backscattering profile can be inferred from correlations between base pairs.  相似文献   

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10.
《Nuclear Physics A》2007,781(1-2):201-208
We discuss forward–backward correlations in the multiplicity of produced particles in heavy ion collisions. We find the color glass condensate generates distinctive predictions for the long range component of this correlation. In particular, we predict the growth of the long range correlation with the centrality of the collision. We argue that the correlation for baryons is less strong than that for mesons.  相似文献   

11.
We discuss the physics of the ridge–azimuthally collimated long range rapidity correlations–in high multiplicity proton–proton and proton–nucleus collisions. We outline some of the theoretical discussions in the literature that address the systematics of these ridge correlations.  相似文献   

12.
Velocity fluctuations of grains flowing down a rough inclined plane are experimentally studied. The grains at the free surface exhibit fluctuating motions, which are correlated over a few grain diameters. The characteristic correlation length is shown to depend on the inclination of the plane and not on the thickness of the flowing layer. This result strongly supports the idea that dense granular flows are controlled by a characteristic length larger than the particle diameter.  相似文献   

13.
Studying nucleon-nucleon (NN) correlated pairs will teach us a great deal about the high momentum part of the nuclear wave function,the short range part of the NN interaction,and the nature of cold dense nuclear matter.These correlations are similar in all nuclei,differing only in magnitude.High momentum nucleons,p 〉p fermi,all have a correlated partner with approximately equal and opposite momentum.At pair relative momenta of 300 〈prel 〈500 MeV/c,these correlated pairs are dominated by tensor correlations.This is shown by the dominance of pn over pp pairs at pair total momentum and by the parity of pn to pp pairs at large pair total momentum.  相似文献   

14.
Studying nucleon-nucleon (NN) correlated pairs will teach us a great deal about the high momentum part of the nuclear wave function, the short range part of the NN interaction, and the nature of cold dense nuclear matter. These correlations are similar in all nuclei, differing only in magnitude. High momentum nucleons, p > pfermi, all have a correlated partner with approximately equal and opposite momentum. At pair relative momenta of 300 < prel < 500 MeV/c, these correlated pairs are dominated by tensor correla-tions. This is shown by the dominance of pn over pp pairs at pair total momentum and by the parity of pn to pp pairs at large pair total momentum.  相似文献   

15.
The inelastic neutron scattering cross section for dense nitrogen gas at several pressures near 240 atmospheres and room temperature has been measured in the region of the first diffraction peak. The Van Hove self-correlation function is calculated from models and subtracted from these cross sections to yield ?S d(Q, ω)/?p. This derivative is related to an integral over the time-dependent triplet correlation function and models for the triplet function are tested. A simple model, based on pair functions, gives moderate agreement.  相似文献   

16.
It is shown that the recently proposed method of studying the long-range correlations in multiparticle production can be effectively used to verify the hydrodynamic nature of the longitudinal expansion of the partonic system created in the collision. The case of ALICE detector is explicitly considered.  相似文献   

17.
The dynamics of star polymers is investigated via extensive molecular and Brownian dynamics simulations for a large range of functionality f and packing fraction eta. The calculated isodiffusivity curves display both minima and maxima as a function of eta and minima as a function of f. Simulation results are compared with theoretical predictions based on different approximations for the structure factor. In particular, the ideal glass transition line predicted by mode-coupling theory is shown to exactly track the isodiffusivity curves, offering a theoretical understanding for the observation of disordered arrested states in star-polymer solutions.  相似文献   

18.
The short-range correlations between nucleons in finite nuclei are investigated in the framework of Glauber multiple scattering theory without any free parameters. The effects on proton-nucleus and nucleus - nucleus interactions such as p - {4}He$ and {4}He- {12}C elastic scattering, and in particular the proton elastic scattering off hallo-like nuclei, {6,8}He, are estimated. Our calculations show that the short-range correlations play an important role in reproducing experimental data and could be also thought of as being the origin and nature of halo-like phenomena in the nuclear structure. More accurate calculations along this line are needed.  相似文献   

19.
A model for diffusion in spaces with ultrametric topology is introduced. The parameters of the model are two sets of numbers: the branching numberm l+1 /m l describing the hierarchical structure of the metric and the transition ratesr l between different levels of the hierarchy. This model is expected to be relevant to the spin glas problem. The exact solution of the dynamical problem can be given in the general case. In the special casem l =m l andr l R l anomalous long time behaviour of the autocorrelation function is found which decays with a power law multiplied by a periodically varying amplitude.Dedicated to B. Mühlschlegel on the occasion of his 60th birthdayThis work has been supported by the Sonderforschungsbereich 125, Aachen-Jülich-Köln  相似文献   

20.
Abstract

New experimental data are presented which indicate the change of defect centers concentration in GaAs at macroscopic (up to millimeters) distances from the implanted regions edge. These data were obtained by locally exited cathodoluminescence, by observation of photoconductivity detected locally by contactless MW technique, by conductivity, DLTS and Raman spectroscopy measurement. Interpretation of the mechanism of long range effect is presented.  相似文献   

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