Development and testing of the optical module for the P-ONE experiment

The P-ONE (Pacific Ocean Neutrino Experiment) is a future cubic-km-scale, water Cherenkov neutrino telescope that will be located in the Pacific Ocean off the coast of Canada. This telescope will contribute to the search for astrophysical neutrino sources, test improved detection and calibration techniques, and provide valuable oceanographic measurements. The first line of the detector, named P-ONE-1, is currently under production.The first line of the detector, named P-ONE-1, is currently in production. The P-ONE Optical Module (P-OM) consists of sixteen 3-inch photomultiplier tubes (PMTs), as well as a series of calibration devices (flashers, acoustic devices, axicons and muon scintillators), which will be used to characterise the optical properties of water and measure the initial performance of the line. The PMT waveforms are digitzed by a 16-channel (210 MHz) analog-to-digital converter (ADC) with a timing system providing an estimated accuracy of 0.1 ns. After assembling the P-OM, it will be essential to characterise and calibrate the different photosensors in order to create an accurate simulation of the mooring line and verify that the modules function properly. Therefore, at the Technical University of Munich a dedicated automatic calibration setup consisting of multiple light sources and a rotation stage was developped to perform quality control of the P-OM hemispheres and measure the properties of the PMTs. This contribution will discuss the different feature and subsystem of the optical module and its measured performance.