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Pallavi Kalikotay

Publications and source records attributed to Pallavi Kalikotay.

4 recordsLinked to original sources

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

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 $ππ\rightarrow ππ$ scattering cross-section calculated using the thermo-magnetic $ρ$ 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.

nucl-th

Dynamics of QCD Matter -- current status

In this article, there are 18 sections discussing various current topics in the field of relativistic heavy-ion collisions and related phenomena, which will serve as a snapshot of the current state of the art. Section 1 reviews experimental results of some recent light-flavored particle production data from ALICE collaboration. Other sections are mostly theoretical in nature. Very strong but transient magnetic field created in relativistic heavy-ion collisions could have important observational consequences. This has generated a lot of theoretical activity in the last decade. Sections 2, 7, 9, 10 and 11 deal with the effects of the magnetic field on the properties of the QCD matter. There are several unanswered questions about the QCD phase diagram. Sections 3, 11 and 18 discuss various aspects of the QCD phase diagram and phase transitions. Recent years have witnessed interesting developments in foundational aspects of hydrodynamics and their application to heavy-ion collisions. Sections 12, 15, 16 and 17 of this article probe some aspects of this exciting field. Transport coefficients together with their temperature- and density-dependence, are essential inputs in hydrodynamical calculations. Sections 5, 8 and 14 deal with calculation/estimation of various transport coefficients (shear and bulk viscosity, thermal conductivity, relaxation times, etc.) of quark matter and hadronic matter. Sections 4, 6 and 13 deals with interesting new developments in the field. Section 4 discusses color dipole gluon distribution function at small transverse momentum in the form of a series of Bells polynomials. Section 6 discusses the properties of Higgs boson in the quark gluon plasma using Higgs-quark interaction. Section 13 discusses modification of coalescence model to incorporate viscous corrections and application of this model.

hep-ph

Medium effects on the electrical and Hall conductivities of a hot and magnetized pion gas

The electrical and Hall conductivities in a uniform magnetic field are evaluated for an interacting pion gas using the kinetic theory approach within the ambit of relaxation time approximation (RTA). The in-medium cross sections vis-a-vis the relaxation time for $ππ$ scattering are obtained using a one-loop modified thermal propagator for the exchanged $ρ$ and $σ$ mesons using thermal field theoretic techniques. For higher values of the magnetic field, a monotonic increase of the electrical conductivity with the temperature is observed. However, for a given temperature the conductivity is found to decrease steadily with magnetic field. The Hall conductivity, at lower values of the magnetic field, is found to decrease with temperature more rapidly than the electrical conductivity, whereas at higher values of the magnetic field, a linear increase is seen. Use of the in-medium scattering cross-section is found to produce a significant effect on the temperature dependence of both electrical and Hall conductivities compared to the case where vacuum cross-section is used.

hep-ph

Viscous coefficients and thermal conductivity of a $πK N$ gas mixture in the medium

The temperature and density dependence of the relaxation times, thermal conductivity, shear viscosity and bulk viscosity for a hot and dense gas consisting of pions, kaons and nucleons have been evaluated in the kinetic theory approach. The in-medium cross-sections for $ππ$, $πK$ and $πN$ scatterings were obtained by using complete propagators for the exchanged $ρ$, $σ$, $K^*$ and $Δ$ excitations derived using thermal field theoretic techniques. Notable deviations can be observed in the temperature dependence of $η$, $ζ$ and $λ$ when compared with corresponding calculations using vacuum cross-sections usually employed in the literature. The value of the specific shear viscosity $η/s$ is found to be in agreement with available estimates.

nucl-th