Detector configuration of KAGRA - the Japanese cryogenic gravitational-wave detector

TL;DR

KAGRA is a Japanese cryogenic gravitational-wave detector with advanced technologies like underground placement, cryogenic cooling, and quantum noise reduction, designed to observe space-time ripples from distant galaxies.

Contribution

This paper details the design, configuration, and parameter selection of KAGRA, highlighting its unique cryogenic and underground features for gravitational-wave detection.

Findings

Successful integration of cryogenic cooling at 20 K

Implementation of quantum non-demolition techniques

Optimized detector configuration for enhanced sensitivity

Abstract

Construction of the Japanese second-generation gravitational-wave detector KAGRA has been started. In the next 6 \sim 7 years, we will be able to observe the space-time ripple from faraway galaxies. KAGRA is equipped with the latest advanced technologies. The entire 3-km long detector is located in the underground to be isolated from the seismic motion, the core optics are cooled down to 20 K to reduce thermal fluctuations, and quantum non-demolition techniques are used to decrease quantum noise. In this paper, we introduce the detector configuration of KAGRA; its design, strategy, and downselection of parameters.