Visualization of spatial profiles of spectra and intensities in FEL simulations

We have developed FEL numerical simulation codes to analyze and examine the FEL experimental results at Electrotechincal Laboratory (ETL) using optical klystrons, and we have reached excellent agreement with experiments so far. To further advance the codes for better and quick understanding, we have tried to visualize the simulation results, especially for spatial profiles of spectra and intensities, using color graphic terminals. Spectral information at each observation point is converted to color graphic data through the modification of a CIE XYZ color system. Simulation results on the color display of the CRT show good agreement with a photo of spontaneous emission spectra taken in the TERAS storage ring at ETL using an optical klystron, and 231 MeV electrons with the fundamental wavelength of 596 nm. Also, the fundamental, 2nd, and 3rd harmonics are separately visualized.