Numerical Simulations of Pair Production by Ultraintense Lasers

Using a combination of particle-in-cell plasma kinetic codes and the CERN GEANT4 code for pair production, we systematically study the pair production by ultraintense lasers irradiating gold targets. We will present results for the pair production yield and spectra as a function of laser and target parameters, and compare simulation results with recent data from Titan and other laser experiments. Using these we will design future experiments to optimize the pair yield and pair density. Potential applications of these results to both laboratory astrophysics and high density positronium physics will be discussed.