ANALYSIS ON VARIATION FACTORS OF OPTICAL POWER AT THE

The near-infrared free electron laser (FEL) at the Laboratory for Electron Beam Research and Application (LEBRA) in Nihon University has been provided for scientific studies in various fields since 2003. The behaviour of the LEBRA electron linac system has been monitored using various diagnostic devices such as beam position monitors, vacuum gauges, thermocouples, optical power monitors and so on. The results obtained during operation of the linac have been routinely stored in databases or files. This paper discusses about the analysis on the factors of fluctuation for the electron beam energy/position and the FEL optical power on the basis of the linac diagnostic results.