Laser Acceleration of Protons Using Multi-ion Plasma Gaseous Targets
Author | : |
Publisher | : |
Total Pages | : |
Release | : 2015 |
ISBN-10 | : OCLC:925456486 |
ISBN-13 | : |
Rating | : 4/5 (86 Downloads) |
Book excerpt: We present a theoretical and numerical study of a novel acceleration scheme by applying a combination of laser radiation pressure and shielded Coulomb repulsion in laser acceleration of protons in multi-species gaseous targets. By using a circularly polarized CO2 laser pulse with a wavelength of 10 [mu]m--much greater than that of a Ti: Sapphire laser--the critical density is significantly reduced, and a high-pressure gaseous target can be used to achieve an overdense plasma. This gives us a larger degree of freedom in selecting the target compounds or mixtures, as well as their density and thickness profiles. By impinging such a laser beam on a carbon-hydrogen target, the gaseous target is first compressed and accelerated by radiation pressure until the electron layer disrupts, after which the protons are further accelerated by the electron-shielded carbon ion layer. An 80 MeV quasi-monoenergetic proton beam can be generated using a half-sine shaped laser beam with a peak power of 70 TW and a pulse duration of 150 wave periods.