High order asymptotic-preserving schemes for the Boltzmann equation

In this note we discuss the construction of high order asymptotic preserving numerical schemes for the Boltzmann equation. The methods are based on the use of Implicit-Explicit (IMEX) Runge-Kutta methods combined with a penalization technique recently introduced in [F. Filbet, S. Jin: A class of asymptotic preserving schemes for kinetic equations and related problems with stiff sources,J. Comp. Phys. 229, (2010), pp. 7625-7648.].