Magnetic evaluation of a developed permanent magnet undulator as a linac-based THz coherent radiation source

TL;DR

This paper presents the design, simulation, fabrication, and magnetic evaluation of a permanent magnet undulator integrated with a 10 MeV linac to generate tunable THz coherent radiation, demonstrating promising results for practical applications.

Contribution

It introduces a newly developed PPM undulator optimized for THz radiation at a linac, with validated magnetic and radiation harmonic calculations.

Findings

Magnetic measurements agree with simulations.

Photon energies from 3 meV to 23 meV achievable.

Undulator design suitable for THz source applications.

Abstract

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.