Overview and Performance of the Wavelength-shifting Optical Module (WOM)

The Wavelength-shifting Optical Module (WOM) is a novel photosensor concept developed in thecontext of the IceCube-Gen2 neutrino telescope, a next generation multi-km$^3$neutrino telescopeat the South Pole. It provides a large photosensitive area with low detector noise and improvedUV sensitivity. This is achieved by combining a wavelength-shifter (WLS) coated tube withtwo small, low-noise PMTs. Incident UV photons are absorbed by the WLS and re-emittedisotropically. A large fraction of the light is captured in the tube by total internal reflection andguided to the small PMTs. Through its cylindrical geometry, which is well matched to the drillholes, this concept results not only in an overall improved detection efficiency, but at the same timesaves production and drilling cost. In this contribution we discuss the performance characteristicsof the WOM and present the current status of the prototype development