Angular momentum and energy spread measurements by backscattering technique

A main interest in the design of a high-intensity particle beam accelerator as the EURISOL driver is the control of the particle losses in the vacuum chamber. These losses, even concerning an extremely low fraction of the beam (10-4-10-7), can be sufficient to considerably complicate the maintenance of such an accelerator. Within this framework and in order to contribute to accelerator projects dedicated to rare isotope physics, the CEA is undertaking a research program on the theoretical and experimental study of the physical processes involved in halo formation around a high intensity beam in a particle accelerator. This research program is performed in collaboration with several French and international laboratories.This note details the principle and the design of an innovative emittance measurement unit which aims to be “weakly” interceptive. “Weakly” means that the beam can continue to propagate in the pipe with similar properties compared to the case when the diagnostic is not inserted. It is planned to compare these emittance measurements to the predictions of the home-made codes which are used to simulate the EURISOL medium and high energy sections.