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arXiv · 1603.01843

A Brief Technical History of the Large-Area Picosecond Photodetector (LAPPD) Collaboration

Abstract

The Large Area Picosecond PhotoDetector (LAPPD) Collaboration was formed in 2009 to develop large-area photodetectors capable of time resolutions measured in pico-seconds, with accompanying sub-millimeter spatial resolution. During the next three and one-half years the Collaboration developed the LAPPD design of 20 x 20 cm modules with gains greater than $10^7$ and non-uniformity less than $15\%$, time resolution less than 50 psec for single photons and spatial resolution of 700~microns in both lateral dimensions. We describe the R\&D performed to develop large-area micro-channel plate glass substrates, resistive and secondary-emitting coatings, large-area bialkali photocathodes, and RF-capable hermetic packaging. In addition, the Collaboration developed the necessary electronics for large systems capable of precise timing, built up from a custom low-power 15-GigaSample/sec waveform sampling 6-channel integrated circuit and supported by a two-level modular data acquisition system based on Field-Programmable Gate Arrays for local control, data-sparcification, and triggering. We discuss the formation, organization, and technical successes and short-comings of the Collaboration. The Collaboration ended in December 2012 with a transition from R\&D to commercialization.

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Bernhard W. Adams, Klaus Attenkofer, Mircea Bogdan, Karen Byrum, Andrey Elagin, Jeffrey W. Elam, Henry J. Frisch, Jean-Francois Genat, Herve Grabas, Joseph Gregar, Elaine Hahn, Mary Heintz, Zinetula Insepov, Valentin Ivanov, Sharon Jelinsky, Slade Jokely, Sun Wu Lee, Anil. U. Mane, Jason McPhate, Michael J. Minot, Pavel Murat, Kurtis Nishimura, Richard Northrop, Razib Obaid, Eric Oberla, Erik Ramberg, Anatoly Ronzhin, Oswald H. Siegmund, Gregory Sellberg, Neal T. Sullivan, Anton Tremsin, Gary Varner, Igor Veryovkin, Alexei Vostrikov, Robert G. Wagner, Dean Walters, Hsien-Hau Wang, Matthew Wetstein, Junqi Xi, Zikri Yusov, Alexander Zinovev. 2016-03-06. A Brief Technical History of the Large-Area Picosecond Photodetector (LAPPD) Collaboration. https://arxiv.org/abs/1603.01843

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