Producing National Ignition Facility (NIF)-quality beams on the Nova and Beamlet Lasers

The Nova and Beamlet Lasers were used to simulate the beam propagation conditions that will be encountered during the National Ignition Facility operation. Perturbation theory predicts that there is a 5 mm scale length propagation mode that experiences large nonlinear power growth. This mode was observed in the tests. Further tests have confirmed that this mode can be suppressed with improved spatial filtering.