Ion acceleration by irradiating an extremely thin target with an intense laser

A large area suspended graphene is irradiated with Vulcan PW laser to produce energetic ions. A single layer graphene has thickness of 1 nm, which is the thinest target in the world. In order to investigate effects of target thickness in nm scales, we prepare single, double, four and eight layer graphene targets. We utilize a double-plasma mirror to suppress the pre pulse. The accelerated ions are detected with a stack of radiochromic films (RCFs) and CR-39. From the RCF stacks, with double and four layer graphene we obtained energetic ions with at least 70 MeV per nuclei. We distinguish the ion species and estimate ion energy with CR-39.レーザー学会学術講演会第38回年次大