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arXiv · 1711.02367

Prototyping Hexagonal Light Concentrators Using High-Reflectance Specular Films for the Large-Sized Telescopes of the Cherenkov Telescope Array

Akira Okumura·Dang Viet Tan·Sakiya Ono·Syunya Tanaka·Masaaki Hayashida·Jim Hinton·Hideaki Katagiri·Koji Noda·Masahiro Teshima·Tokonatsu Yamamoto·Tatsuo Yoshida
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Abstract

We have developed a prototype hexagonal light concentrator for the Large-Sized Telescopes of the Cherenkov Telescope Array. To maximize the photodetection efficiency of the focal-plane camera pixels for atmospheric Cherenkov photons and to lower the energy threshold, a specular film with a very high reflectance of 92-99% has been developed to cover the inner surfaces of the light concentrators. The prototype has a relative anode sensitivity (which can be roughly regarded as collection efficiency) of about 95 to 105% at the most important angles of incidence. The design, simulation, production procedure, and performance measurements of the light-concentrator prototype are reported.

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Akira Okumura, Dang Viet Tan, Sakiya Ono, Syunya Tanaka, Masaaki Hayashida, Jim Hinton, Hideaki Katagiri, Koji Noda, Masahiro Teshima, Tokonatsu Yamamoto, Tatsuo Yoshida. 2017-11-07. Prototyping Hexagonal Light Concentrators Using High-Reflectance Specular Films for the Large-Sized Telescopes of the Cherenkov Telescope Array. https://doi.org/10.1088/1748-0221%2F12%2F12%2Fp12008

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