The study of the aging behavior on large area MCP-PMT

TL;DR

This study investigates the aging behavior of large area MCP-PMTs through long-term experiments, measuring spectral responses and resistance changes, and develops a model to describe the aging process.

Contribution

The paper presents the first detailed aging analysis of large area MCP-PMTs and proposes a general aging formula based on experimental data.

Findings

Aging is strongly related to MCP properties.

Aging curve and model were established.

Accelerated aging tests validated the model.

Abstract

Aging experiments of a novel type of large area MCP-PMT made by JUNO collaboration were conducted.In these aging experiments, the multi-photoelectron spectrum and single photoelectron spectrum were measured daily,as well as the MCP resistance of the second PMT before and after the experiment. Two PMTs were aged successivelyfor cross check. The first PMT was aged for 52 days, while the other one was aged for 84 days. In order to study the mechanism of the aging process, the high voltage on the second PMT was increased to accelerate its aging process when the cumulative output of charge from its anode was about 4 C. From our study, it can be known that large area MCP-PMT aging had a strong relationship with the related MCPs. In accordance with the PMT aging curve,a PMT aging model was setup and a general aging formula was given.