Transport Coefficients of Dense Stellar Plasma in Strong Magnetic Field

Abstract

Following an exact relativistic formalism (Ghosh et al. in Ann Phys 312, 398 (2004) [1]), we study the transport properties of dense stellar electron-proton plasma in a strong quantizing magnetic field. The transport coefficients, namely the coefficients of shear and bulk viscosities as well as thermal and electrical conductivities are obtained from the relativistic version of Boltzmann kinetic equation by linearizing the distribution function and using relaxation time approximation. The dependence of the kinetic coefficients on the strength of the magnetic field is discussed. The variation of these coefficients with magnetic fields are found to be insensitive for the field strengths $\le$ $10^{17}$G beyond which decreases with magnetic field. As a consequence, in presence of ultra-strong magnetic field, the electron-proton plasma behaves like a superfluid insulator. Since the electrical conductivity of the medium becomes extremely low (almost zero) in presence of ultra-strong magnetic field, the magnetic field at the core region must, therefore, decay very quickly. Hence, strong magnetic field can not exist at the core of magnetars.