Landau–Khalatnikov Problem in Relativistic Fluid Dynamics

Abstract

An alternative method is proposed for solving the Landau–Khalatnikov problem of the 1D expansion stage of a hot hadron matter formed during collisions of high-energy particles or atomic nuclei. The solution of relativistic fluid dynamics equations by the Riemann method gives a new representation for the Khalatnikov potential, in which the symmetry of the emerging flow to reflection in the central plane of the initial distribution of the matter is observed. New exact relations that describe the evolution of the energy density at the center of the distribution as well as the motion of boundaries between the general solution and expansion waves are derived. The energy and velocity distributions of particles, including the preexponential factors that have not been considered earlier, are obtained in the Landau approximation.