Laser-plasma proton accelerators

Ion acceleration with lasers has also shown significant progress in recent years. The production of proton beams from laser interactions with solid targets has been well studied with existing laser systems. HiPER will provide not only the ability to operate at high energies and ultra high intensities but also to provide very wide focal spots, and thus proton beams. Laser-induced production of protons at very high intensities has tremendous promise because the proton beam becomes highly directional with increasing laser intensity. More sophisticated configurations, such as multilayer targets also make it possible to generate protons having energy spread of ~5%. Fast ions (mainly fast protons) provide a wealth of applications (fast ignition, plasma accelerators, medicine, nuclear physics, physics of elementary particles). Furthermore, at higher laser intensities the direct ion probing techniques of dense matter (plasmas) are becoming an important diagnostic technique, allowing proton radiography of imploding thermonuclear targets. The development of direct ion probing techniques to obtain information on shock parameters, such as density, would allow precise absolute EOS determinations and would represent a real breakthrough in the field.