13 research outputs found
Probing Fractionalized Charges
Inspired by holographic entanglement entropy, for geometries with non-zero
abelian charges, we define a quantity which is sensitive to the background
charges. One observes that there is a critical charge below that the system is
mainly described by the metric and the effects of the background charges are
just via metric's components. While for charges above the critical one the
background gauge field plays an essential role. This, in turn, might be used to
define an order parameter to probe phases of a system with fractionalized
charges.Comment: Latex file, 17 pages, 7 figures, Published versio
Meson Life Time in the Anisotropic Quark-Gluon Plasma
In the hot (an)isotropic plasma the meson life time is defined as a
time scale after which the meson dissociates. According to the gauge/gravity
duality, this time can be identified with the inverse of the imaginary part of
the frequency of the quasinormal modes, , in the (an)isotropic black
hole background. In the high temperature limit, we numerically show that at
fixed temperature(entropy density) the life time of the mesons
decreases(increases) as the anisotropy parameter raises. For general case, at
fixed temperature we introduce a polynomial function for and observe
that the meson life time decreases. Moreover, we realize that ,
where and are entropy density and temperature of the plasma
respectively, can be expressed as a function of anisotropy parameter over
temperature. Interestingly, this function is a Pad\'{e} approximant.Comment: 5 pages, 4 figures, 1 tabl
Hydrodynamic excitations in hot QCD plasma
We study the long wavelength excitations in rotating QCD fluid in the presence of an external magnetic field at finite vector and axial charge densities. We consider the fluctuations of vector and axial charge currents coupled to energy and momentum fluctuations and compute the SO(3) covariant dispersion relations of the six corresponding hydrodynamic modes. Among them, there are always two scalar chiralmagnetic- vortical-heat (CMVH) waves; in the absence of a magnetic field (vorticity) these waves reduce to chiral-vortical-heat (CVH) [chiral-magnetic-heat (CMH)] waves. While CMVH waves are a mixture of CMH and CVH waves, they have generally different velocities compared to the sum of velocities of the latter waves. The other four modes, which are made out of scalar-vector fluctuations, are mixed soundAlfven waves. We show that when the magnetic field is parallel with the vorticity, these four modes are the two ordinary sound modes together with two chiral Alfven waves propagating along the common direction of the magnetic field and vorticity
Holographic Phase Transition to Topological Dyons
The dynamical stability of a Julia-Zee solution in the AdS background in a
four dimensional Einstein-Yang-Mills-Higgs theory is studied. We find that the
model with a vanishing scalar field develops a non-zero value for the field at
a certain critical temperature which corresponds to a topological dyon in the
bulk and a topological phase transition at the boundary.Comment: 18 pages, 2 figures, 2 tables, sections 2 and 4 are shortened, an
error in the last part of section 5 is corrected and equations are modified.
This version to be published in JHE
Standardized cumulants of flow harmonic fluctuations
The distribution of flow harmonics in heavy-ion experiment can be characterized by standardized cumulants. We first model the ellipticity and power parameters of the elliptic-power distribution by employing MC-Glauber model. Then we use the elliptic-power distribution together with the hydrodynamic linear response approximation to study the two dimensional standardized cumulants of elliptic and triangular flow (v(2) and v(3)) distribution. For the second harmonic, it turns out that finding two-dimensional cumulants in terms of 2q-particle correlation functions c(2){2q} is limited to the skewness. We also show that c(3){2}, c(3){4}, and c(3){6}, are related to the second, fourth, and sixth standardized cumulants of the v(3) distribution, respectively. The cumulant c(n){2q} can be also written in terms of v(n) {2q}. Specifically, -(v(3){4}/v(3){2})(4) turns out to be the kurtosis of the v(3) event-by-event fluctuation distribution. We introduce a new parametrization for the distribution p(v(3)) with v(3){2}, kurtosis and sixth-order standardized cumulant being its free parameters. Compared to the Gaussian distribution, it indicates a more accurate fit with experimental results. Finally, we compare the kurtosis obtained from simulation with that of extracted from experimental data for the v(3) distribution