Complex light source composed from subterahertz-wave coherent synchrotron radiation and an infrared free-electron laser at the Laboratory for Electron Beam Research and Application

We have successfully transported subterahertz-wave (sub-THz-wave) coherent synchrotron radiation (CSR) from an accelerator room to an experimental room by using an existing IR free-electron laser (FEL) beamline at the Laboratory for Electron Beam Research and Application at Nihon University. The power of the transported CSR was 50 nJ per macropulse, and it was available at frequencies of 0.1-0.3 THz. From two-dimensional imaging performed with the sub-THz-wave CSR, metallic structures concealed by plastic in a smart card were nondestructively detected at a spatial resolution of 1.4 mm. We also verified the existence of hydrated water in a crystal by using chemometric two-band spectroscopy with the sub-THz-wave CSR and IR FEL. Pioneering applications, such as more reliable material identification, can be anticipated from this complex light source composed from the sub-THz-wave CSR and IR FEL beams.