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arXiv · 2403.05165

Electrical conductivity and shear viscosity of a pion gas in a thermo-magnetic medium

Pallavi Kalikotay·Snigdha Ghosh·Nilanjan Chaudhuri·Pradip Roy·Sourav Sarkar
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Abstract

We evaluate the electrical conductivity and shear viscosity of a interacting pion gas in a thermo-magnetic medium using the kinetic theory. The collision term of the relativistic Boltzmann transport equation in presence of background magnetic field is solved using the relaxation time approximation. The medium modified relaxation time is obtained from the corresponding in-medium $\pi\pi\rightarrow \pi\pi$ scattering cross-section calculated using the thermo-magnetic $\rho$ propagator. It is observed that the average relaxation time shows a $1/T^4$ variation with temperature for a fixed value of magnetic field. The relaxation time shows a mild oscillatory variation with respect to the magnetic field. It is also observed that the medium dependent scattering cross-section causes a considerable amount of influence on the electrical conductivity and shear viscosity compared to its vacuum counterpart.

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Pallavi Kalikotay, Snigdha Ghosh, Nilanjan Chaudhuri, Pradip Roy, Sourav Sarkar. 2024-03-08. Electrical conductivity and shear viscosity of a pion gas in a thermo-magnetic medium. https://doi.org/10.1140/epja/s10050-024-01291-w

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