Characterization of Two PMT Models for the IceCube Upgrade mDOM

TL;DR

This paper characterizes two different PMT models intended for use in the IceCube Upgrade's multi-PMT optical modules, analyzing their performance metrics across temperature ranges to inform selection.

Contribution

It provides detailed comparative characterization data for two PMT models, aiding in the selection process for the IceCube Upgrade's optical modules.

Findings

Both PMTs have suitable gain and quantum efficiency for the application.

Dark noise rates vary with temperature and differ between models.

Timing characteristics meet the requirements for neutrino detection.

Abstract

The IceCube Upgrade will expand the IceCube Neutrino Observatory with nearly 800 new optical modules. A large fraction of these will be multi-PMT optical modules (mDOMs), featuring 24 PMTs pointing uniformly in all directions, providing an almost homogeneous angular coverage and providing an effective photosensitive area more than twice that of current IceCube optical modules. Two PMT models from different manufacturers are currently considered for use in the mDOM: a 3.5 inch PMT from HZC Photonics and a 3 inch PMT from Hamamatsu. Both PMTs have been characterized in terms of gain, timing, quantum efficiency and dark noise rate as a function of temperature. The obtained characterization results are presented here.