Modeling of the double pass X-ray laser: Effects on its focalization

In this article we describe a new ray-trace code. This code is a three-dimensional description of the beam propagation, including the half cavity mirror. It is based on the integration of the ray equation and on the calculation of the intensity along the plasma. It works as a postprocessor of the hydrodynamic/atomic code "EHYBRID," which calculates the time evolution of the gain, emissivity, electronic density, and the width of the plasma. We present results obtained on different schemes of X-ray laser generation.