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arXiv · 1907.12785

Influence of non-uniformity in sapphire substrates for a gravitational wave telescope

Kentaro Somiya·Eiichi Hirose·Yuta Michimura
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Abstract

Construction of a large-scale cryogenic gravitational-wave telescope KAGRA has been completed and the four sapphire test masses have been installed in cryostat vacuum chambers. It recently turned out that a sapphire substrate used for one of the input test masses shows a characteristic strcuture in its transmission map due to non-uniformity of the crystal. We performed an interferometer simulation to see the influence of the non-uniformity using measured transmission/reflection maps.

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Kentaro Somiya, Eiichi Hirose, Yuta Michimura. 2019-07-30. Influence of non-uniformity in sapphire substrates for a gravitational wave telescope. https://doi.org/10.1103/physrevd.100.082005

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