Direct-drive laser fusion in the United States of America

Direct-drive experiments at the University of Rochester's Laboratory for Laser Energetics (LLE) and the Naval Research Laboratory (NRL) address issues in pellet compression and heating: efficiency of the coupling of laser energy to the target and the coupling of absorbed energy to the fuel, drive uniformity, hydrodynamic stability, preheat arising from laser plasma instabilities and x-rays, and target diagnostics. The 24 beam, 2500 J, 351 nm OMEGA laser system at LLE has been used in an experimental effort to achieve high compressed DT fuel densities. Detailed hydrodynamic computer simulations at NRL predict that the growth rate of the ablative Rayleigh-Taylor instability is less than the classical values. Recent Rayleigh-Taylor experiments at NRL test these predictions. (author). 18 refs, 2 figs, 1 tab