arXiv subjects

Bing-feng Jiang

Publications and source records attributed to Bing-feng Jiang.

4 recordsLinked to original sources

arXiv2026

Heavy quark collisional energy loss in a nonextensive quark-gluon plasma

In this study, we derive the longitudinal and transverse gluon self-energies and the corresponding dielectric functions for a nonextensive QGP, based on nonextensive statistical mechanics and a kinetic theory framework. The nonextensive parameter $q$ enters these quantities primarily through the modification of the Debye mass. Utilizing the derived dielectric functions, we then calculate the collisional energy loss for a heavy quark using two established formalisms: the plasma physics-based Thoma-Gyulassy formula and the thermal field theory-originated Kirzhnits-Thoma formula. Our results show that for both formalisms, the collisional energy loss increases with the nonextensive parameter $q$ with this enhancement being more significant at higher incident quark momenta and suppressed for a heavier quark mass. The energy loss predicted from the Kirzhnits-Thoma formula is substantially larger than that from the Thoma-Gyulassy formula, and the nonextensive effect on the energy loss is more pronounced in the former. Furthermore, the mass suppression of the nonextensive effect on the energy loss is weaker in the Kirzhnits-Thoma approach. These calculations demonstrate that nonextensive statistics can significantly alter the energy loss in the QGP.

hep-ph↗

arXiv2025

Electromagnetic responses of a non-extensive quark-gluon plasma

Based on the non-extensive statistical mechanics and the gluon polarization tensor obtained from kinetic theory, we derive the longitudinal and transverse gluon self-energies for the quark-gluon plasma. The electric permittivity $\varepsilon$ and the magnetic permeability $μ_M$ are evaluated from the gluon self-energies through which the real part of the square of the refraction index ${\rm Re}\, n^2$ and the Depine-Lakhtakia index $n_{DL}$ are investigated. The real part of $\varepsilon$ displays a frequency pole $ω_d=p$, which is just the position of the frequency inflexion of the imaginary part of $\varepsilon$. The non-extensive parameter $q$ significantly affects the real and imaginary parts of $\varepsilon$ in the space-like region $ω<p$, while the frequency pole $ω_d=p$ remains unchanged as $q$ increases. The magnetic permeability, ${\rm Re}\, n^2$ and the Depine-Lakhtakia index $n_{DL}$ diverge at frequency $ω_m$. As $q$ increases, the pole frequency $ω_m$ shifts to large frequency region. The Depine-Lakhtakia index $n_{DL}$ becomes negative in a quite large frequency region $ω\in[ω_c, ω_m]$. When $q$ increases, the frequency range for $n_{DL}<0$ becomes wider. Nevertheless, there are no propagating modes for the negative refraction. In addition, as momentum $p$ increases, the electric permittivity, the magnetic permeability, ${\rm Re}\, n^2$ and $n_{DL}$ are sensitive to the change of $p$, which indicates the importance of the spatial dispersion in the electromagnetic responses of the QGP.

hep-ph↗

arXiv2021

Color-electric conductivity in a viscous quark-gluon plasma

Several different transport processes, such as heat transport, momentum transport and charge transport, may take place at the same time in the quark-gluon plasma (QGP). The corresponding transport coefficients are heat conductivity, shear viscosity and electric conductivity respectively. In the present paper, we will study the color-electric conductivity of the QGP in presence of shear viscosity, which is focused on the connection between the charge transport and the momentum transport. To achieve that goal, we solve the viscous chromohydrodynamic equations which are obtained from the QGP kinetic theory associated with the distribution function modified by shear viscosity. According to the solved color fluctuations of hydrodynamic quantities we obtain the induced color current through which the color-electric conductivity is derived. Then we study viscous effects on the color-electric conductivity. In the viscous chromohydrodynamic approach, the conductivity properties of the QGP are mainly demonstrated by the longitudinal part of the color-electric conductivity. Shear viscosity has an appreciable impact on real and imaginary parts of the color-electric conductivity in some frequency region.

hep-ph↗

arXiv2013

The refractive index in the viscous quark-gluon plasma

Under the framework of the viscous chromohydrodynamics, the gluon self-energy is derived for the quark-gluon plasma with shear viscosity. The viscous electric permittivity and magnetic permeability are evaluated from the gluon self-energy, through which the refraction index %in the %viscous quark-gluon plasma is investigated. The numerical analysis indicates that the refractive index becomes negative in some frequency range. The start point for that frequency range is around the electric permittivity pole, and the magnetic permeability pole determines the end point. As the increase of $η/s$, the frequency range for the negative refraction becomes wider.

hep-ph↗