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arXiv · 1010.1057

Lifetime-Extended MCP-PMT

T. Jinno·T. Mori·T. Ohshima·Y. Arita·K. Inami·T. Ihara·H. Nishizawa·T. Sasaki
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Abstract

In order to develop a long-lifetime MCP-PMT under high rates of circumstance, we investigated the degradation of the quantum efficiency (QE) of PMT's with a multialkali photocathode. We found that not only positive ions, but also neutral residual gases would damage the photocathode resulting in an enhancement of the work function; their countermeasures were established in newly manufactured square-shaped MCP-PMT's with 4 or 4x4 multi-anodes. The performances of the PMT's were measured: QE was stable up to an integrated amount of anode output charge of 2-3 C/cm^2, while keeping other basic performances steady, such as the time resolution for single photons of ~40 ps, a photoelectron collection efficiency (CE) of 60%, a multiplication gain (G) of a few x 10^6, and dark counts of 20-300 Hz. The causes of QE degradation are discussed.

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T. Jinno, T. Mori, T. Ohshima, Y. Arita, K. Inami, T. Ihara, H. Nishizawa, T. Sasaki. 2010-10-06. Lifetime-Extended MCP-PMT. https://doi.org/10.1016/j.nima.2010.10.145

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