Speaker
Description
KAGRA participated in the international collaborative observation run, O4a, for a duration of one month, concluding in June 2023. Currently, the observatory is in the commissioning phase, preparing for subsequent observations. With KAGRA's sensitivity on the rise, precise calibration becomes paramount for accurate scientific results. We utilize auxiliary lasers to apply radiation pressure, injecting reference signals into the interferometer through the Photon Calibration (Pcal) system for calibration purposes. We have been responsible for developing and maintaining this system.
Significant enhancements have been made to KAGRA's Pcal system since the previous observation run, O3, aimed at minimizing uncertainty. Improvements include estimating the power and the position of the Pcal laser on the end test masse (ETM) of the Pcal laser, essential for calibration accuracy. Moreover, in the transition to O4, plans are underway to enhance the reliability of absolute laser power measurements through a global calibration effort involving LVK, NIST, and PTB, aimed at improving measurement accuracy and reliability.
