Enhanced proton emission and hot electron dynamics inside Cu and Au flat-top cone (FTC) targets

10 $\mu $m thick Au and Cu FTC targets were shot recently at LANL on the Trident laser at 80-100 J, $\sim $600 fs and $\sim $5x10$^{19 }$W/cm$^{2}$. These initial results are compared to previous experiments on Trident at $\sim $20 J and $\sim $1x10$^{19 }$W/cm$^{2}$ using similar Au FTCs which yielded higher conversion efficiencies (4.5{\%}) and proton energies (30 MeV) compared to 15 $\mu $m Au flat foils (0.75{\%}, 19 MeV) [K. A. Flippo \textit{et al.}, PoP \textbf{14} (2008)]. To elucidate the physics of electron transport and proton beam enhanced emission, Cu-K$\alpha $ imaging and spectroscopy are used to observe the laser absorption and electron heating, and the Cu FTCs are compared to similar funnel-only cones resulting in an enhancement in the electron density toward the cone tip [J. Rassuchine \textit{et al.}, PRL submitted (2008)].