Hydrodynamic shocks produced by the ICF scale laser beams in flowing, underdense plasmas.

High energy randomized laser beams interacting with flowing plasmas can produce a plasma response that leads to beam bending and, by momentum conservation, to slowing down of the plasma flow velocity [1]. For the incoming plasma flow, with a velocity slightly greater than sound speed, the plasma response to a ponderomotive force exerted by speckled laser beams is the strongest, such that slowing down of the flow to subsonic velocities leads to the formation of a shock. Using hydrodynamic simulations and the scaling laws we will discuss designs of experiments on NIF and OMEGA facilities that will demonstrate bow shock formation and allow to verify theoretical predictions. Simulations have shown large density and velocity jumps for the LEH parameters on NIF. The necessary condition for the shock to be formed is the presence of the sonic velocity in the transverse flow across the laser beam. We will specify the required power and size of the interacting beams. Interaction of the expanding gold plasma in a hohlraum glint experiment will be examined for the shock generation.

[1] H.A. Rose, Phys. Plasmas 3, 1709 (1996).