Continuous production of a thin ribbon of solid hydrogen

Abstract

AbstractThe development of very high power laser opens up new horizons in a various field, such as protontherapy in medicine or laser-matter interaction in physics. The Target Normal Sheath Acceleration phenomenon is used in the first one. After the laser-matter impact, a plasma is generated, and free electrons move forward. It creates an electrostatic field, which can accelerate protons at the rear side of the target. The generated beam can be able to contain energetic protons with a large spectrum(1–200 MeV). This energy distribution depends on the laser power and the nature of the target. This technique has been validated by accelerating protons coming from hydrogenated contaminant (mainly water) at the rear of metallic target up to 58 MeV at Lawrence Livermore National Laboratory using the Nova Petawatt laser. However, several laser teams would like to study this interaction with pure targets. In this context, the low temperature laboratory, at CEA-Grenoble has developed a cryostat able to continuously produce a thin hydrogen ribbon (50 and 100 μm thick). A new extrusion concept, without any moving part has been carried out, using only the thermodynamic properties of the fluid. First results and perspectives are presented in this paper.