Electron Linac Upgrade for Thomx Project

The injector Linac for Thomx * consists of an electron gun and S-band accelerating section. The RF gun is a 2.5 cells photo-injector able to provide electron bunches with 5 MeV energy. During the commissioning phase, a standard S-band accelerating section is able to achieve around 50 MeV corresponding to around 45 keV X-rays energy. Since the maximum targeted X-ray energy is 90 keV, the Linac design will provide a beam energy of 70 MeV. The Linac upgrade of the machine covers many different aspects. The purpose is to increase the compactness of the accelerator complex whereas the beam properties for ring injection are kept. A LAL Orsay-PMB ALCEN collaboration has been established. The program foresees the RF design, prototyping and power tests of a high-gradient compact S-band accelerating structure. To fulfill the technical specifications at the interaction point, the Linac must be carefully designed. Beam dynamics simulations have been performed for optimizing the emittance and the energy spread for the ring entrance. The best set of parameters together with the effect of the accelerating section to the beam dynamics at the end of the LINAC will be presented.