View Factor and Radiation-Hydrodynamic Simulations of Gas-Filled Outer-Quad-Only Hohlraums at the National Ignition Facility*

A cylindrical National Ignition Facility hohlraum irradiated exclusively by NOVA-like [1] outer quads ($44.5^{\circ}$ and $50^{\circ}$ beams) is proposed to minimize laser plasma interaction (LPI) losses and avoid problems with propagating the inner ($23.5^{\circ}$ and $30^{\circ}$) beams. Symmetry and drive are controlled by shortening the hohlraum, using a smaller laser entrance hole (LEH), beam phasing the $44.5^{\circ}$ and $50^{\circ}$ beams [2-3], and correcting the remaining $P_4$ asymmetry with a capsule shim [4]. Ensembles of time-resolved view factor simulations [5] help narrow the design space of the new configuration, with fine tuning provided by the radiation-hydrodynamic code HYDRA. [1] L.~J.~Suter, et al., Phys.~Rev.~Lett.~73, 2328 (1994). [2] R.~E.~Turner, et al., Phys.~Plasmas~7, 333 (2000). [3] S.~G.~Glendinning, et al., Rev.~Sci. Instrum.~70, 536 (1999). [4] D.~S.~Clark, et al., Phys.~Plasmas~23, 072707 (2016). [5] J.~J.~MacFarlane, J. Quant.~Spectr.~Rad.~Transfer 81, 287 (2003).