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arXiv · 1906.02866

Prospects for improving the sensitivity of KAGRA gravitational wave detector

Yuta Michimura·Masaki Ando·Eleonora Capocasa·Yutaro Enomoto·Raffaele Flaminio·Sadakazu Haino·Kazuhiro Hayama·Eiichi Hirose·Yousuke Itoh·Tomoya Kinugawa·Kentro Komori·Matteo Leonardi·Norikatsu Mio·Koji Nagano·Hiroyuki Nakano·Atsushi Nishizawa·Norichika Sago·Masaru Shibata·Hisaaki Shinkai·Kentaro Somiya·Hiroki Takeda·Takahiro Tanaka·Satoshi Tanioka·Li-Wei Wei·Kazuhiro Yamamoto
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Abstract

KAGRA is a new gravitational wave detector which aims to begin joint observation with Advanced LIGO and Advanced Virgo from late 2019. Here, we present KAGRA's possible upgrade plans to improve the sensitivity in the decade ahead. Unlike other state-of-the-art detectors, KAGRA requires different investigations for the upgrade since it is the only detector which employs cryogenic cooling of the test mass mirrors. In this paper, investigations on the upgrade plans which can be realized by changing the input laser power, increasing the mirror mass, and injecting frequency dependent squeezed vacuum are presented. We show how each upgrade affects to the detector frequency bands and also discuss impacts on gravitational-wave science. We then propose an effective progression of upgrades based on technical feasibility and scientific scenarios.

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BibTeXRIS

Yuta Michimura, Masaki Ando, Eleonora Capocasa, Yutaro Enomoto, Raffaele Flaminio, Sadakazu Haino, Kazuhiro Hayama, Eiichi Hirose, Yousuke Itoh, Tomoya Kinugawa, Kentro Komori, Matteo Leonardi, Norikatsu Mio, Koji Nagano, Hiroyuki Nakano, Atsushi Nishizawa, Norichika Sago, Masaru Shibata, Hisaaki Shinkai, Kentaro Somiya, Hiroki Takeda, Takahiro Tanaka, Satoshi Tanioka, Li-Wei Wei, Kazuhiro Yamamoto. 2019-06-07. Prospects for improving the sensitivity of KAGRA gravitational wave detector. https://doi.org/10.1142/9789811258251_0236

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