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arXiv · 1604.07738

Development and testing of cost-effective, 6 cm x 6 cm MCP-based photodetectors for fast timing applications

Abstract

Micro-channel plate (MCP)-based photodetectors are capable of picosecond level time resolution and sub-mm level position resolution, which makes them a perfect candidate for the next generation large area photodetectors. The large-area picosecond photodetector (LAPPD) collaboration is developing new techniques for making large-area photodetectors based on new MCP fabrication and functionalization methods. A small single tube processing system (SmSTPS) was constructed at Argonne National Laboratory (ANL) for developing scalable, cost-effective, glass-body, 6 cm x 6 cm, picosecond photodetectors based on MCPs functionalized by Atomic Layer Deposition (ALD). Recently, a number of fully processed and hermitically sealed prototypes made of MCPs with 20 micron pores have been fabricated. This is a significant milestone for the LAPPD project. These prototypes were characterized with a pulsed laser test facility. Without optimization, the prototypes have shown excellent results: The time resolution is ~57 ps for single photoelectron mode and ~15 ps for multi-photoelectron mode; the best position resolution is < 0.8 mm for large pulses. In this paper, the tube processing system, the detector assembly, experimental setup, data analysis and the key performance will be presented.

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Jingbo Wang, Karen Byrum, Marcel Demarteau, Jeffrey Elam, Anil Mane, Edward May, Robert Wagner, Dean Walters, Junqi Xie, Lei Xia, Huyue Zhao. 2016-04-26. Development and testing of cost-effective, 6 cm x 6 cm MCP-based photodetectors for fast timing applications. https://arxiv.org/abs/1604.07738

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