The Recent status of the development of laser-driven proton accelerator for medical use

Nishiuchi, Mamiko

The proton beam attracts many potential fields of applications. This is because the laser-driven proton has many peculiar characteristics if compared with those of from the conventional accelerators. The report that the acceleration of the proton beam is successfully upto 120 MeV is reported with single shot base large laser system. The objective for us is to obtain the proton beam with energy more than 100 MeV with compact repetitive laser system. We have achieved 40 MeV proton beam with laser parameters of 8 J, 40 fs, contrast ratio of more than 10 and the peak intensity upto 10Wcm is focused onto the stainless steal tape target of 2 um. The energy conversion efficiency from laser to protons with energy more than 15 MeV is about 0.1%. We are now able to provide repetitive 40 MeV proton beam by more than 1Hz rep rate.