Influence of nonuniformity in sapphire substrates for a gravitational wave telescope

@article{Somiya2019InfluenceON,
  title={Influence of nonuniformity in sapphire substrates for a gravitational wave telescope},
  author={Kentaro Somiya and Eiichi Hirose and Yuta Michimura},
  journal={Physical Review D},
  year={2019}
}
The construction of a large-scale cryogenic gravitational wave telescope, KAGRA, has been completed, and four sapphire test masses have been installed in cryostat vacuum chambers. Recently, it was observed that a sapphire substrate used for one of the input test masses showed a characteristic structure in its transmission map due to nonuniformity of the crystal. We performed an interferometer simulation to observe the influence of the nonuniformity using measured transmission/reflection maps… 
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