PoS(PhotoDet2015)022 The development and performance evaluation of a hybrid photo-detector for Hyper-Kamiokande Miao JIANG * Department of Physics, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan E-mail: mjiang@scphys.kyoto-u.ac.jp Yasuhiro NISHIMURA a , Yuji OKAJIMA b , Masahiro KUZE b , Yusuke SUDA c , Ryosuke AKUTSU c , Daisuke FUKUDA d , Seiko HIROTA, Masashi YOKOYAMA c , Masayuki NAKAHATA a , Masato SHIOZAWA a , Yoshinari HAYATO a , Shoei NAKAYAMA a , Hidekazu TANAKA a , Tsuyoshi NAKAYA, Akihiro MINAMINO, Akimichi TAKETA e , Yoshihiko KAWAI f , Takayuki OHMURA f , Masatoshi SUZUKI f a Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582, Japan b Department of Physics, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8551, Japan c Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan d Department of Physics, Okayama University, Okayama, Okayama 700-8530, Japan e Earthquake Research Institute, University of Tokyo, Bunkyo-ku, Tokyo 113-0032, Japan f Hamamatsu Photonics K.K., Hamamatsu, Shizuoka, 430-8587, Japan We have been developing a new hybrid photo-detector (HPD) for Hyper-Kamiokande, which is a proposed next generation megaton-class water Cherenkov detector. The prototypes of the 50 cm HPD with φ 5 mm avalanche diode (AD) [1] and the 50 cm HPD with φ 20 mm AD (R12850, Hamamatsu Photonics K.K.) were designed and produced after successful fabrication of 20 cm HPD. For the 50 cm HPD with φ 5 mm AD, the transit time spread, linearity and temperature dependence of gain have been evaluated. For our target design of the 50 cm HPD with φ 20 mm AD, two solutions by the segmented AD and the transformer coupling were tried to suppress the capacity seen by preamplifier since it is difficult to design a high speed preamplifier with low noise level for a large area AD due to the large junction capacitance. They successfully reduced the noise, and the performance of HPD showed significant improvements. International Conference on New Photo-detectors - PhotoDet 2015 6-9 July 2015 Moscow, Troitsk, Russia * Speaker. c Copyright owned by the author(s) under the terms of the Creative Commons Attribution 4.0 licence. http://pos.sissa.it/ © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). http://pos.sissa.it/