4,603 research outputs found
Chiral magnetic currents with QGP medium response in heavy ion collisions at RHIC and LHC energies
We calculate the electromagnetic current with a more realistic approach in
the RHIC and LHC energy regions in the article. We take the partons formation
time as the initial time of the magnetic field response of QGP medium. The
maximum electromagnetic current and the time-integrated current are two
important characteristics of the chiral magnetic effect (CME), which can
characterize the intensity and duration of fluctuations of CME. We consider the
finite frequency response of CME to a time-varying magnetic field, find a
significant impact from QGP medium feedback, and estimate the generated
electromagnetic current as a function of time, beam energy and impact
parameter.Comment: 10 pages, 12 figur
Multifractal analysis of weighted networks by a modified sandbox algorithm
Complex networks have attracted growing attention in many fields. As a
generalization of fractal analysis, multifractal analysis (MFA) is a useful way
to systematically describe the spatial heterogeneity of both theoretical and
experimental fractal patterns. Some algorithms for MFA of unweighted complex
networks have been proposed in the past a few years, including the sandbox (SB)
algorithm recently employed by our group. In this paper, a modified SB
algorithm (we call it SBw algorithm) is proposed for MFA of weighted
networks.First, we use the SBw algorithm to study the multifractal property of
two families of weighted fractal networks (WFNs): "Sierpinski" WFNs and "Cantor
dust" WFNs. We also discuss how the fractal dimension and generalized fractal
dimensions change with the edge-weights of the WFN. From the comparison between
the theoretical and numerical fractal dimensions of these networks, we can find
that the proposed SBw algorithm is efficient and feasible for MFA of weighted
networks. Then, we apply the SBw algorithm to study multifractal properties of
some real weighted networks ---collaboration networks. It is found that the
multifractality exists in these weighted networks, and is affected by their
edge-weights.Comment: 15 pages, 6 figures. Accepted for publication by Scientific Report
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