• G.L. Orlandi, B. Beutner, R. Ischebeck, V. Schlott, B. Steffen
  PSI, Villigen

Diagnostics with a transverse spatial resolution in the order or even higher than the intrinsic limit of the traditional OTR light spot imaging techniques is required for high energy and low emittance electron beams by FEL driver linac. High resolution measurements of the beam transverse size can be performed by moving the radiation detection from the space of the electron transverse coordinates to the Fourier conjugate space of the radiation angular distribution. The development of such a new diagnostic technique is related to the experimental investigation of the beam transverse size effects in the angular distribution of the OTR spectral intensity. The status of the experimental investigation of such a phenomenon at the SwissFEL project and the main features of such a new diagnostic technique will be presented.