Commissioning of Strong Tapered Undulator Developed for Ifel Accelerator

Here we describe the manufactured KIAE-2p planar undulator designed for the Inverse Free Electron Laser experiment at the University of California in Los Angeles. New technology enabled to fabricate the installation responding to the stringent requirements on mechanical construction accuracy and magnetic field strong tapering. Results of the magnetic field measurements by different methods are given. The obtained magnetic field maps were used for final simulations of the acceleration process. It is shown that for nominal electron beam and laser beam parameters up to 30% of electrons can be captured and accelerated from initial 14 MeV up to 52 MeV. Special analysis of the undulator acceptances for these parameters is made. It is shown that the acceleration is possible up to energies >30 MeV for rather wide ranges of laser pulse energy, Rayleigh length and e.b. emittance.