“Rise and Shine”: Exploring a hypothesis that may unify Au sphere and NIF hohlraum modeling *

We use a liberal electron transport flux limiter, (~ 0.1) to match the high level of x-ray emission (at the end of a 1 ns pulse) from Au spheres driven by the URLLE Omega laser at 1.0 E15 W/sq-cm. But, NIF hohlraums with similar first bounce laser irradiances within it, have capsules imploding later than predicted by such a model. Severely restricted the flux limit (~ 0.02) can reproduce such implosion times. How to reconcile this paradox is a lingering question. Here we explore the following hypothesis. A high leverage part of the NIF hohlraum pulse is on the rise to peak power. A delay of the x-ray emission during that time can significantly delay the implosion time. It turns out that in the rise to peak power of the Au spheres there is also an apparent delay in the x-ray emission. This may be due to LPI processes, or it may be due to early time transport problems, that can be characterized as severely flux limited (~ 0.02) early on. The spheres then relax to a liberal flux limit (~ 0.1) later in the pulse. This “Rise and Shine” model reproduces the late time x-ray emission, while being consistent with implosion time delays in the NIF hohlraum, thus unifying the 2 data sets.