Multicomponent second-order dissipative relativistic hydrodynamics with binary reactive collisions

We derive the multicomponent second-order dissipative relativistic hydrodynamic equations using the moment-expansion method. By computing the transport coefficients using hard-sphere interactions, we investigate the role of multiple components and the reactive collisions. We find that both of these factors increase the effective cross section and hence decrease the transport coefficients and relaxation times. We further compute such transport properties using leading-order perturbative QCD cross sections. For both types of cross sections, we find that the ratio between vector current relaxation time and conductivity for a multicomponent fluid is notably different from that for a single-component fluid. Therefore, the current study provides a more applicable guideline for such a ratio in phenomenological hydrodynamics simulations.