An Efficient Source of Relativistic Electrons for Medical Applications

3 An Efficient Source of Relativistic Electrons for Medical Applications 

Three dimensional particle-in-cell simulation performed with the numerical code CALDER [77] reveals that the unprecedented efficiency of this accelerator was due to the achievement of a physical regime in which multiple electron bunches are accelerated in the gas-jet plasma during the action of each laser shot. This effect is shown in Fig. 8.7 by a snap-shot from the simulation sequence. 

With this experiment, laser-driven electron acceleration approaches the stage of suitability for medical uses, in particular for Intra-Operative Radiation Therapy (IORT) of tumors [78,79]. Comparison of the main parameters of electron bunches produced by two commercial RF Hospital accelerators for IORT treatment and those of this laser-driven accelerator is shown in the Table 8.1. Most of the performances of the experimental laser-driven electron accelerator set-up at CEA-Saclay are comparable with presently used conventional accelerators. Notice that, though the dose delivered for each shot is also comparable, the electron bunch duration is about six orders of 

Accelerator type IORT-NOVAC7 LIAC Laser-driven accelerator 

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