PPPS-2013: Emittance and emission from arrays with statistical variation

Abstract

Summary form only given. We report on the incorporation of a model of field emitters based on a Point Charge Model (PCM)1 that allows for rapid and analytical representations of tip current, variation, and emission statistics and its implementation and usage in the MICHELLE Particle-In-Cell (PIC) code2 to model the impact of emission variation on current characteristics and emittance. Rather than cold field emission characterized by the Fowler Nordheim equation, a General Thermal-Field (GTF) emission model3 treats warm and hot field emission sources. We shall compare the increases in emittance and beam radius due to emission non-uniformity as modeled by assuming a LogNormal (LN) distribution of emitter geometries4. The consequences for high frequency devices shall be explored.