Gamma rays transmutation of Palladium by bremsstrahlung and laser inverse Compton scattering

Photo-transmutation of hazardous long lived radioactive 107Pd induced by bremsstrahlung and Compton scattering is carried out. Photonuclear reactions is investigated by irradiating a 2 mm tantalum target with a 1021 W cm−2 μm2 laser intensity into a 1 cm thick 107Pd target placed directly behind it. Based on the reported data by intense and well-collimated gamma photon beams generated by inexpensive inverse Compton scatterings of a 100 W CO2 laser and the 3.5 GeV high energy electron, a suitable theoretical formalism is presented. The scattered energy and the differential cross section are characterized as a function of scattering angle. It is found that the number of reactions in the Compton backscattering method is about 30 orders magnitude better than the one for bremsstrahlung method for 1021 W cm−2 μm2 laser intensity with 10 Hz repetition rate for half hour irradiation time. In addition, the strongly dependence of transmutation reaction rate on the laser characters, irradiation time and energy of outgoing electron beam is shown and the optimal effective parameters to produce the maximum number of reactions are evaluated.