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 φ5 mm avalanche diode (AD)  and the 50 cm HPD with φ20 mm AD (R12850, Hamamatsu Photonics K.K.) were designed and produced after successful fabrication of 20 cm HPD. For the 50 cm HPD with φ5 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 φ20 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.
|Journal||Proceedings of Science|
|Publication status||Published - 2015|
|Event||4th International Conference on New Photo-Detectors, PhotoDet 2015 - Moscow, Troitsk, Russian Federation|
Duration: 2015 Jul 6 → 2015 Jul 9
ASJC Scopus subject areas