Feasibility of optical diffraction radiation for a non-invasive low-emittance beam diagnostics

A “proof-of-principle” experiment on the optical diffraction radiation (ODR) as a single-pulse beam profile monitor is planned using an electron beam extracted from the KEK-ATF damping ring. The main goals of this experiment are the following: measure the yield and the angular distributions of the optical diffraction radiation from a large-size target at different wavelengths, impact parameters and beam characteristics for a comparison with analogous characteristics of optical transition radiation from a foil with identical optical parameters and for a verification of the model assumption (perfectly conducting semi-infinite target). o investigate the ODR angular distributions from a tilted target with a slit for observing the interference effects. To compare the results obtained by simulations based on classical approaches, taking into account the optical characteristics of the equipment and the beam parameters. o estimate the prospects of using ODR as a new non-invasive tool for ultrarelativistic beams. imated that the ODR photon yield in 10% bandwidth for 500 nm is about 106 photons/bunch with an impact parameter of 100 μm. This indicates that the ODR monitor is a promising candidate for single-pulse beam-profile measurements, and that it will be an extremely useful instrument for future linear colliders (JLC, NLC, TESLA and CLIC).