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arXiv · 2107.10194

The Wavelength-shifting Optical Module (WOM) for the IceCube Upgrade

Abstract

The Wavelength-shifting Optical Module (WOM) is a novel optical sensor that uses wavelength shifting and light guiding to substantially enhance the photosensitive area of UV optical modules. It has been designed for the IceCube Upgrade, a seven-string extension of the IceCube detector planned for the 2022/2023 South Pole deployment season. The WOM consists of a hollow quartz cylinder coated in wavelength shifting paint which serves as detection area and has two photomultipliers (PMTs) attached to the end faces. The light-collecting tube increases the effective photocathode area of the PMTs without producing additional dark current, making it suitable for low-signal, low-noise applications. We report on the design and performance of the WOM with a focus on the 12 modules in production for deployment in the IceCube Upgrade. While the WOM will be deployed in IceCube, its design is applicable to any large-volume particle detector based on the detection of Cherenkov light.

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John Rack-Helleis, Anna Pollmann, Martin Rongen. 2021-07-21. The Wavelength-shifting Optical Module (WOM) for the IceCube Upgrade. https://arxiv.org/abs/2107.10194

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