Photo-transmutation of long-lived nuclear waste 135Cs by intense Compton γ-ray source

Abstract

MeV-range Compton γ-ray beam via Compton scattering of a laser pulse against a high-current relativistic electron beam can be used to induce photo-transmutation reactions. In this work, we investigate through Monte Carlo simulations the possibility of transmutation of radioactive nuclear waste, by high-intensity Compton γ-ray source, for the long-lived 135Cs with a half-life of 2.3 × 106 years into short-lived 134Cs with a half-life of 2.07 years, or into stable nuclide 133Cs. Our simulation results show that the transmutation reaction yield is in the order of 6 × 109 per hour for a given γ-flux of 2 × 108 phs/s that can be obtained from the Shanghai Laser Electron Gamma-ray Source which is under construction. The transmutation capability of worldwide Compton γ-ray facilities is also evaluated, showing that the photo-transmutation induced by brilliant Compton γ-ray source, such as ELI-NP could be an efficient approach to transmute long-lived radioactive nuclear waste.