The objective is to develop a detector to measure the energy of ultra-relativistic charged particles. By measuring the angular distribution of x-rays emitted when a charged particle passes through a stack of foils (transition radiation) the efficiency of the detector and energy determination can be improved over simply counting the number of photons. The linear accelerator at the Naval Postgraduate School in Monteray California will be used to explore the angular resolution to separate the transition radiation from the incoherent radiation. The coherent radiation would be a source of x-rays for ultra-relativistic electron detection.