Abstract
The first direct detection of gravitational waves was achieved by the Laser Interferometer Gravitational-Wave Observatory (LIGO) in 2015. LIGO, comprising two detectors located in the United States, employs laser interferometry to detect gravitational waves. The initial observation successfully detected gravitational waves emitted during the merger of two black holes. Subsequently, LIGO and Virgo have observed over 100 gravitational wave events in previous observations.
In April 2024, LIGO, Virgo initiated later part of the worldwide gravitational wave observation O4, O4-b. To minimize systematic uncertainty, we have contributed to the calibration and reconstruction study in this observation. In particular, we achieve to unify two formula of sensing function in calibration model. This presentation aims to provide an overview of the current status of the calibration study and discuss future in LIGO.