Overview of KAGRA: Calibration, detector characterization, physical environmental monitors, and the geophysics interferometer

Abstract KAGRA is a newly built gravitational wave observatory, laser interferometer with 3 km arm length, located at Kamioka, Gifu, Japan. In this series of articles we present an overview the baseline KAGRA, for which finished installing designed configuration in 2019. This article describes method calibration (CAL) used reconstructing signals from detector outputs, as well characterization (DET). We also review physical environmental monitoring (PEM) system and geophysics (GIF). Both are characterizing evaluating data quality channel. They play important roles utilizing output searches. These investigations will be even more near future, once detection has been achieved, using astronomy era.