Polar tent for reduced perturbation of NIF ignition capsules

In simulations, a tent that contacts the capsule near the poles and departs tangential to the capsule surface greatly reduces the capsule perturbation, and the resulting mass injected into the hot-spot, compared to current capsule support methods. Target fabrication appears feasible with a layered tent (43-nm polyimide $+$ 8-nm C) for increased stiffness. We are planning quantitative measurements of the resulting shell-$\rho $R perturbation near peak implosion velocity (PV) using enhanced self-emission backlighting, achieved by adding \textasciitilde 1{\%} Ar to the capsule fill in Symcaps ($^{\mathrm{4}}$He $+$ H). Layered DT implosions are also planned for an integrated test of capsule performance. We will describe the design and simulation predictions.