The status of KAGRA underground cryogenic gravitational wave telescope

TL;DR

KAGRA is a groundbreaking underground cryogenic gravitational wave detector in Japan, utilizing seismic noise reduction and cryogenic cooling, with initial operations completed and full interferometer observations anticipated in the 2020s.

Contribution

This paper reports the construction and current status of KAGRA, the first underground and cryogenic km-class gravitational wave telescope, highlighting its unique design features and operational progress.

Findings

Construction of KAGRA infrastructure completed

Initial interferometer operation achieved

Full interferometer observations expected in 2020s

Abstract

KAGRA is a 3-km interferometric gravitational wave telescope located in the Kamioka mine in Japan. It is the first km-class gravitational wave telescope constructed underground to reduce seismic noise, and the first km-class telescope to use cryogenic cooling of test masses to reduce thermal noise. The construction of the infrastructure to house the interferometer in the tunnel, and the initial phase operation of the interferometer with a simple 3-km Michelson configuration have been completed. The first cryogenic operation is expected in 2018, and the observing runs with a full interferometer are expected in 2020s. The basic interferometer configuration and the current status of KAGRA are described.