  Continuum kinetic simulations of plasmas, where the distribution function of
the species is directly discretized in phase-space, permits fully kinetic
simulations without the statistical noise of particle-in-cell methods. Recent
advances in numerical algorithms have made continuum kinetic simulations
computationally competitive. This work presents the first continuum kinetic
description of high-fidelity wall boundary conditions that utilize the readily
available particle distribution function. The boundary condition is realized
through a reflection function that can capture a wide range of cases from
simple specular reflection to more involved first principles models. Examples
with detailed discontinuous Galerkin implementation are provided for secondary
electron emission using phenomenological and first-principles
quantum-mechanical models. Results presented in this work demonstrate the
effect of secondary electron emission on a classical plasma sheath.
