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arXiv · 1112.5084

Development of transparent silica aerogel over a wide range of densities

Makoto Tabata·Ichiro Adachi·Yoshikazu Ishii·Hideyuki Kawai·Takayuki Sumiyoshi·Hiroshi Yokogawa
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Abstract

We have succeeded in developing hydrophobic silica aerogels over a wide range of densities (i.e. refractive indices). A pinhole drying method was invented to make possible producing highly transparent aerogels with entirely new region of refractive indices of 1.06-1.26. Obtained aerogels are more transparent than conventional ones, and the refractive index is well controlled in the pinhole drying process. A test beam experiment was carried out in order to evaluate the performance of the pinhole-dried aerogels as a Cherenkov radiator. A clear Cherenkov ring was successfully observed by a ring imaging Cherenkov counter. We also developed monolithic and hydrophobic aerogels with a density of 0.01 g/cm^3 (a low refractive index of 1.0026) as a cosmic dust capturer for the first time. Consequently, aerogels with any refractive indices between 1.0026 and 1.26 can be produced freely.

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Makoto Tabata, Ichiro Adachi, Yoshikazu Ishii, Hideyuki Kawai, Takayuki Sumiyoshi, Hiroshi Yokogawa. 2011-12-21. Development of transparent silica aerogel over a wide range of densities. https://doi.org/10.1016/j.nima.2010.02.241

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