Design and operation of a setup with a camera and adjustable mirror to inspect the sense-wire planes of the Time Projection Chamber inside the MicroBooNE cryostat

TL;DR

This paper presents a camera and mirror setup designed to visually inspect the sense-wire planes inside the MicroBooNE cryostat, enabling damage detection without opening the vessel.

Contribution

It introduces a novel inspection system using a camera and adjustable mirror through cryogenic nozzles for internal detector visualization.

Findings

Successful inspection of sense-wire planes demonstrated

System effectively identified damage or sagging

Setup operated reliably within cryogenic environment

Abstract

Detectors in particle physics, particularly when including cryogenic components, are often enclosed in vessels that do not provide any physical or visual access to the detectors themselves after installation. However, it can be desirable for experiments to visually investigate the inside of the vessel. The MicroBooNE cryostat hosts a TPC with sense-wire planes, which had to be inspected for damage such as breakage or sagging. This paper describes an approach to view the inside of the MicroBooNE cryostat with a setup of a camera and a mirror through one of its cryogenic service nozzles. The paper describes the camera and mirror chosen for the operation, the illumination, and the mechanical structure of the setup. It explains how the system was operated and demonstrates its performance.