Intense ion beams accelerated by petawatt-class lasers

The LLNL Petawatt Laser has achieved focused intensities up to 6 by 10 20 W/cm 2 . IN plasmas created by this laser, the quiver energy of target electrons exceed several MeV. Recent experiments revealed an intense, collimated beam of high-energy is converted into protons which leads to an energy content of 30J in a pulse of less than 10 ps. The beam shows a broad particle energy spectrum with a sharp cut off and an almost mono-energetic part above 55 MeV. With their short pulse duration, high particle energy and large luminosity these beams are promising candidates in numerous applications, such as short-pulse injectors for laser accelerators or as the ignitor for fast ignition ICF. Using intense proton beams the fast ignitor concept may also become more attractive in heavy-ion fusion due to the possibility to work with indirectly driven targets. Finally, the acceleration is not restricted to protons and the use of tailored target surfaces may allow to accelerate more massive ions to similar energy per nucleon.