Development of the DLA Platform on the ARC/NIF with the PHELIX as a Testbed

Direct laser acceleration (DLA) of electrons in plasma of near critical electron density (NCD) is used to generate ultra-bright sources of MeV particles and radiation. In experiments at PHELIX performed at moderate relativistic intensity of ~ 10$^{19}$ W/cm$^{2}$, we were able to demonstrate the generation of well-directed relativistic electrons with energies up to 100 MeV and ~  $\mu$C charge, production of ultra-bright Bremsstrahlung with photon energies of up to 50-60 MeV with the record-breaking conversion efficiency of 2-3 % for photons > 7.5 MeV (giant dipole resonance), ultra-intense betatron radiation and enhanced proton acceleration (super-charged TNSA).

As part of the NIF Discovery Science Program, Plasma Physics, in collaboration with NIF and ENEA groups, submitted an experimental project entitled “Ultra-bright MeV photon sources driven by direct laser accelerated (DLA) electrons on ARC.” Pilot shots on the PHELIX with an ARC-like intensity of 10$^{18}$ W/cm$^{2}$ and a pulse duration of 6 ps, aimed at producing DLA electrons and bright MeV bremsstrahlung, showed promising results for the development of the DLA platform at NIF.