Ion Beams from Short Pulse Laser Irradiation for Fast Ignition

The ePLAS implicit/hybrid code is being used to model fast ion generation for ignition in targets irradiated by short pulse lasers. The code calculates \textit{E{\&}B-}Fields by the implicit moment method\footnote{R. J. Mason, JCP \textbf{71,} 429 (1987) and R. J. Mason, PRL \textbf{96,} 035001 (2006).} and couples electrons to ions at corrected Spitzer rates with variable Z from the Sesame Tables. The moderate to low Z ions are modeled as either PIC particles or a fluid. Typical laser illumination is from 5 x 10$^{19}$ to 3 x 10$^{20}$W/cm$^{2}$ in 1-10 Picosecond pulses, 7 -- 40 $\mu $m in diameter. We will discuss results for a variety of illumination schemes and tuning options to focus and collect the ions, including the use of multiple shells and beams.