Development of beam-pointing stabilizer on a 10-TW Ti:Al2O3 laser system JLITE-X for laser-excited ion accelerator research

We developed a beam-pointing stabilizer for a 10-TW Ti:sapphire laser system to study laser-induced ion acceleration. We confirmed the improvement in the laser beam pointing stability by using a 10-TW laser system (we call it JLITE-X) at JAERI-APRC. The original long-term pointing stability on a 10-TW laser system is similar to 70 mu rad without beam stabilizing. By using a beam-pointing stabilizer, the laser beam stability was improved within 10 mu rad. If f/1 focusing optics and a target which is tilted 45 degrees to the target normal is used, the fluctuation of the laser intensity at the focus will be improved from 80% without stabilizing to < 0.4% with it.