Quantifying heavy quark transport coefficients with an improved transport model

The systematic derivation of transport coefficients for the semi-classical two-component strongly coupled plasma is presented. Starting from a detailed kinetic memory function formulation, a hydrodynamic projection operator method is applied to find a transport model equivalent to the two-Sonine polynomial approximation. The electron thermal conductivity K, d.c. electrical conductivity σ, and the thermoelectric power coefficient are expressed in terms of exact static correlation functions, which are calculated in the hypernetted chain approximation. Numerical values of k and σ are given and comparisons are made with other theories and molecular dynamics simulations of strongly coupled hydrogen. Predictions of σ and k for strongly coupled carbon are also presented.

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Non-isothermal Moisture Transport calculations with DIM 3.1 / Nicht-isotherme Berechnungen des Feuchtigkeitstransportes mit Hilfe des Porgrammes DIM 3.1

Restoration of Buildings and Monuments ◽

10.1515/rbm-2000-5487 ◽

2000 ◽

Vol 6 (4) ◽

pp. 367-384

Author(s):

J. Grunewald ◽

R. Plagge

Keyword(s):

Water Vapour ◽

Liquid Water ◽

Balance Equation ◽

Constitutive Equations ◽

Moisture Transport ◽

Moisture Transfer ◽

Transport Model ◽

Transport Coefficients ◽

Equation System ◽

Transport Processes

Abstract The application of a general thermodynamical mass and energy transport model to the coupled heat and moisture transfer in porous materials results in a balance equation system and the related constitutive equations of the considered quantities. The constitutive equations describe moisture transport in a phase-separated manner leading into phase-divided hygric transport coefficients (liquid water permeability, water vapour diffusivity). A conceptual model is presented in the paper in order to circumvent the difficulties resulting from non-isothermal overlaying moisture transport processes. Since phase-divided hygric transport coefficients are not directly measurable, but moisture transport coefficients in distinct hygric ranges, moisture conductivities and a phase dividing function are introduced. The moisture conductivities include liquid water and water vapour transport. For a known phase dividing function, the phase-divided hygric transport coefficients of the balance equation system can be calculated from the measurable moisture conductivities. The influence of a variation of the introduced phase-dividing function on non-isothermal moisture transport processes is investigated by means of computer simulations.

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Non-perturbative Approach to Equation of State and Collective Modes of the QGP

EPJ Web of Conferences ◽

10.1051/epjconf/201817205001 ◽

2018 ◽

Vol 172 ◽

pp. 05001

Author(s):

Shuai Y.F. Liu ◽

Ralf Rappxs

Keyword(s):

Equation Of State ◽

Heavy Quark ◽

Bound States ◽

Degrees Of Freedom ◽

Transport Coefficients ◽

Gluon Plasma ◽

Spectral Functions ◽

Full Account ◽

Perturbative Approach ◽

Parton Scattering

We discuss a non-perturbative T-matrix approach to investigate the microscopic structure of the quark-gluon plasma (QGP). Utilizing an effective Hamiltonian which includes both light- and heavy-parton degrees of freedoms. The basic two-body interaction includes color-Coulomb and confining contributions in all available color channels, and is constrained by lattice-QCD data for the heavy-quark free energy. The in-medium T-matrices and parton spectral functions are computed selfconsistently with full account of off-shell properties encoded in large scattering widths. We apply the T-matrices to calculate the equation of state (EoS) for the QGP, including a ladder resummation of the Luttinger-Ward functional using a matrix-log technique to account for the dynamical formation of bound states. It turns out that the latter become the dominant degrees of freedom in the EoS at low QGP temperatures indicating a transition from parton to hadron degrees of freedom. The calculated spectral properties of one- and two-body states confirm this picture, where large parton scattering rates dissolve the parton quasiparticle structures while broad resonances start to form as the pseudocritical temperature is approached from above. Further calculations of transport coefficients reveal a small viscosity and heavy-quark diffusion coefficient.

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Elastic vs. radiative heavy quark energy loss within a transport model

Nuclear Physics A ◽

10.1016/j.nuclphysa.2014.07.024 ◽

2014 ◽

Vol 932 ◽

pp. 247-252 ◽

Cited By ~ 2

Author(s):

Jan Uphoff ◽

Oliver Fochler ◽

Zhe Xu ◽

Carsten Greiner

Keyword(s):

Energy Loss ◽

Heavy Quark ◽

Transport Model ◽

Quark Energy Loss

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Drag force on heavy quarks and spatial string tension

Modern Physics Letters A ◽

10.1142/s0217732318500414 ◽

2018 ◽

Vol 33 (06) ◽

pp. 1850041 ◽

Cited By ~ 4

Author(s):

Oleg Andreev

Keyword(s):

String Duality ◽

Drag Coefficient ◽

Heavy Quark ◽

Quark Gluon Plasma ◽

Diffusion Coefficients ◽

Transport Coefficients ◽

Gluon Plasma ◽

String Tension ◽

Heavy Quarks ◽

Strongly Coupled

Heavy quark transport coefficients in a strongly coupled Quark–Gluon Plasma can be evaluated using a gauge/string duality and lattice QCD. Via this duality, one can argue that for low momenta the drag coefficient for heavy quarks is proportional to the spatial string tension. Such a tension is well-studied on the lattice that allows one to straightforwardly make non-perturbative estimates of the heavy quark diffusion coefficients near the critical point. The obtained results are consistent with those in the literature.

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