# Reactor Modelling

We have hypothesized that the photoemission currents during VUV irradiation vary with dielectric thickness due to a difference in the surface potential generated across the dielectric layer. To quantify this, we develop a model that predicts the surface potential across the dielectric layers from the photoemission and substrate currents. The model solves the two-dimensional Laplace equation using the finite-difference method. In order to determine the trajectory of photoemitted electrons, effect of electric field on electrons was included.