Speaker
Dr
Fuyuki Tokanai
(Yamagata University)
Description
A sealed gaseous photomultiplier tube (PMT) with a CsI photocathode has been developed using a micropattern gas detector (MPGDs) made of Pyrex glass. By employing a microblasting technique completely different from that used in microchannel plate (MCP) production, we successfully produced the new hole-type MPGD using Pyrex glass (microblasted glass plate: MB-GP). The glass is well suited for the high level of cleanliness and the reaction conditions required for the production of alkali photocathodes. To evaluate the characteristics of the MB-GP, we constructed a sealed gaseous PMT with CsI photocathode fabricated onto a Quartz glass. We investigated the gaseous PMTs with the semi-transparent CsI photocathode for two different gas mixtures of Ne (90%) + i-C4H10 (10%) and Ne (90%) + CF4 (10%) at a gas pressure of 700 torr. Gains of up to 10^5 were attained with the cascaded MB-GP for both neon gas mixtures. Quantum efficiencies of up to 0.5% were obtained for UV lights at the wavelength of 170 nm. The gaseous PMT provides a fast charge signal with a 22 ns rise time for the scintillation light from a BaF2 crystal irradiated with a 90Sr source. This latest result and the basic performance of the gaseous PMTs are described.
Summary (Additional text describing your work. Can be pasted here or give an URL to a PDF document):
http://ksprite.kj.yamagata-u.ac.jp/~tokanai/Y/summary_VCI-2010-FT2.pdf
Primary author
Dr
Fuyuki Tokanai
(Yamagata University)
Co-authors
Prof.
Hirohisa Sakurai
(Yamagata University)
Mr
Hiroyuki Sugiyama
(Hamamatsu Photonics K. K.)
Mr
Noboru Ohishi
(Hamamatsu Photonics K. K.)
Prof.
Shuichi Gunji
(Yamagata University)
Dr
Shunji Kishimoto
(KEK)
Prof.
Takayuki Sumiyoshi
(Tokyo Metropolitan University)
Mr
Teruyuki Okada
(Hamamatsu Photonics K. K.)
Mr
Yasuo Ohishi
(Hamamatsu Photonics K. K.)
