PRODUCTION OF THERMAL PHOTONS IN A SIMPLE CHIRAL-HYDRODYNAMIC MODEL

We use a self-consistent chiral-hydrodynamic formalism which combines the linear σ model with second-order hydrodynamics in 2 + 1 dimensions to compute the spectrum of thermal photons produced in Au+Au collisions at [Formula: see text]. The temperature-dependent shear viscosity of the model, η, is calculated from the linearized Boltzmann equation. We compare the results obtained in the chiral-hydrodynamic model to those obtained in the second-order theory with a Lattice QCD equation of state and a temperature-independent value of η/s. We find that the thermal photon production is significantly larger in the latter model due to a slower evolution and larger dissipative effects.

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Second-order structural phase transitions, free energy curvature, and temperature-dependent anharmonic phonons in the self-consistent harmonic approximation: Theory and stochastic implementation

Physical Review B ◽

10.1103/physrevb.96.014111 ◽

2017 ◽

Vol 96 (1) ◽

Cited By ~ 37

Author(s):

Raffaello Bianco ◽

Ion Errea ◽

Lorenzo Paulatto ◽

Matteo Calandra ◽

Francesco Mauri

Keyword(s):

Free Energy ◽

Phase Transitions ◽

Approximation Theory ◽

Structural Phase ◽

Harmonic Approximation ◽

Second Order ◽

The Self ◽

Structural Phase Transitions ◽

Temperature Dependent ◽

Self Consistent

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Extremely correlated Fermi liquids: Self-consistent solution of the second-order theory

Physical Review B ◽

10.1103/physrevb.87.245101 ◽

2013 ◽

Vol 87 (24) ◽

Cited By ~ 11

Author(s):

Daniel Hansen ◽

B. Sriram Shastry

Keyword(s):

Order Theory ◽

Second Order ◽

Fermi Liquids ◽

Self Consistent ◽

Consistent Solution

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A slip model for gas lubrication based on an effective viscosity concept

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1243/135065003765714836 ◽

2003 ◽

Vol 217 (3) ◽

pp. 187-195 ◽

Cited By ~ 13

Author(s):

Y. H. Sun ◽

W. K. Chan ◽

N. Y. Liu

Keyword(s):

Boltzmann Equation ◽

Effective Viscosity ◽

Microelectromechanical Systems ◽

Second Order ◽

Slip Effect ◽

Slip Model ◽

Order Model ◽

First Order ◽

Linearized Boltzmann Equation ◽

Gas Lubrication

Gas lubrication theory is used widely in microelectromechanical systems such as microbearings, micropumps and microvalves. Because of microsize or even nanosize geometries, rarefaction and compressible effects will have an impact on the viscosity on flow in these devices. In this paper, the concept of effective viscosity is taken into account for non-continuum flows. The influence of the effective viscosity is incorporated in the analytical solutions of plane Poiseuille flow and flow in inclined channels. The results obtained in the slip, transition and free molecular regimes are compared with the existing first-order and second-order slip models and the linearized Boltzmann equation. It was found that the first-order model underestimates the slip effect while the second-order model overestimates the slip effect. The results obtained from the proposed slip model provide a more accurate approximation to the linearized Boltzmann equation.

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Viscosity to entropy ratio of QGP in relativistic heavy ion collisions: The second-order viscose hydrodynamics

International Journal of Modern Physics E ◽

10.1142/s0218301316500774 ◽

2016 ◽

Vol 25 (10) ◽

pp. 1650077

Author(s):

Sharareh Mehrabi Pari ◽

Fatemeh Taghavi Shahri ◽

Kurosh Javidan

Keyword(s):

Experimental Data ◽

Shear Viscosity ◽

Density Ratio ◽

Heavy Ion ◽

Entropy Density ◽

Second Order ◽

Relativistic Heavy Ion Collisions ◽

Temperature Dependent ◽

Suppression Factor ◽

Ion Collisions

The nuclear suppression factor [Formula: see text] and elliptic flow [Formula: see text] are calculated by considering the effects of shear viscosity to the entropy density ratio [Formula: see text], using the viscose hydrodynamics at the first- and second-orders of approximation and considering temperature dependent coupling [Formula: see text]. It is shown that the second-order viscose hydrodynamics (varying shear viscosity to entropy ratio) with averaged value of [Formula: see text] gives the best results of [Formula: see text] and [Formula: see text] in comparison to the experimental data.

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