  Due to the various applications of THz sources, we developed a pure permanent
magnet (PPM) undulator with 8 periods and min/max values of gap equal to 15/25,
to use at the end of our current 10 MeV linear accelerator (linac) in order to
produce THz coherent radiation. We used RADIA for simulation and calculation of
our magnet and B2E code for calculation of its radiation harmonics. After
fabrication, we also measured the magnetic field via high precision Hall
probes. Calculations and measurements are in good agreements. These
calculations show that it is possible to reach photon energies from 3 meV to 23
meV in the THz region.
