Binoy krishna Patra | Searcharxiv

arXiv2024

Thermoelectric response of a hot and weakly magnetized anisotropic QCD medium

We have studied the Seebeck and Nernst coefficients of a weakly magnetized hot QCD medium having a weak momentum anisotropy within the kinetic theory approach. The thermal medium effects have been incorporated in the framework of a quasi-particle model where the medium dependent mass of the quark has been calculated using perturbative thermal QCD in the presence of a weak magnetic field which leads to different masses for the left ($L$) and right ($R$) handed chiral quark modes. We have found that the Seebeck and Nernst coefficient magnitudes for the individual quark flavors as well as for the composite medium are decreasing functions of temperature and decreasing functions of anisotropy strength. The Nernst coefficient magnitudes are about an order of magnitude smaller than their Seebeck counterparts, indicating the Seebeck effect constitutes a stronger response than the Nernst effect. The average percentage change corresponding to switching between quasiparticle modes ($L\to R$ or $R\to L$) is an order of magnitude smaller for Nernst coefficients, compared to the Seebeck coefficients.

hep-ph↗

arXiv2024

Dynamics of heavy flavour in a weakly magnetized hot QCD medium

We obtain the spatial and momentum diffusion coefficients ($D_s$ and $κ$), and the collisional energy loss ($dE/dx$) of a heavy quark (HQ) traversing through a thermal medium of quarks and gluons in a weak magnetic field ($B$), for the two cases of the HQ moving either parallel or perpendicular to $\bm{B}$. For that purpose, we consider Coulomb scatterings ($t$-channel) of the HQ with the light quarks, obtained from the imaginary part of the HQ self-energy via the cutting rules. Both the normalised (by $T^3$) %\textit{momentum} diffusion coefficients, $κ$, as well as $dE/dx$, for charm quarks are larger than that for bottom quarks due to the larger mass of the latter. Also, the effect of $B$ is more feeble on the bottom quark, compared to the charm quark. Comparatively, the magnitudes of both $κ$ and $dE/dx$ are significantly smaller for the case of $\bm{v}\perp\bm{B}$. For both the cases, our results show that the momentum transfer between the HQ and the medium takes place preferentially along the direction of HQ velocity, thus leading to a significant increase in the momentum diffusion anisotropy, compared to $B=0$. We also calculate the (scaled) spatial diffusion coefficient, which we find to be independent of the heavy flavor mass and is almost unaffected by changes in $B$.

hep-ph↗