Preliminary results of the redesigned Reshock experiment at the OMEGA laser facility

The redesigned LANL OMEGA \textit{Reshock} campaign is exploring the effects of turbulent mixing due to the Richtmyer-Meshkov (RM) instability as part of an ongoing effort to assess the LANL radiation-hydrocode the BHR mix model in the high-energy density regime. Platform improvements have been made to increase the precision of the instability growth measurements. The experiments are conducted in similar geometry to the previous \textit{Reshock} campaigns. A cylindrical beryllium tube is filled with a low-density CH-foam ($\rho \approx $100-150 mg/cc) and a higher density tracer layer that is displaced from an endcap. Two tracer materials have been tested: a low-density plastic ($\rho _{\mathrm{0}}=$1.5 g/cc) layer 40\textmu m thick, and an HDC layer ($\rho_{\mathrm{0}}=$3.2 g/cc) 15 \textmu m thick. The tracer layers have been $\rho $r matched to the previously used aluminum tracer ($\rho _{\mathrm{0}}=$2.43 g/cc). In this platform two shockwaves are generated from opposite ends of the shock tube by a $\approx $5 kJ laser pulse, with time delay $\Delta $t$\approx $3-6ns between them. The primary shockwave generates the initial mixing between the tracer layer and surrounding foam. The second shock leads to a compression of the initial mix layer and to increased turbulence. We will present both initial design simulations for shock timing and tracer choice and preliminary data from the first shot day.