Overview
- An international team deployed six of seven planned upgrade strings between December 2025 and January 2026 into roughly 2.4–2.6 kilometer deep boreholes using a 5‑megawatt hot‑water drill.
- Approximately 670 multi-PMT Digital Optical Modules were installed, each housing 24 photomultiplier tubes oriented in all directions plus high‑resolution cameras for ice characterization.
- The new sensors provide 360‑degree optical coverage and significantly enhance detection of lower‑energy neutrinos, supporting improved reconstruction and neutrino‑oscillation measurements.
- German groups including DESY, KIT, RWTH Aachen, TU Dortmund, and several universities led key sensor development and calibration efforts, with DESY building about 230 of the final detectors.
- The upgrade acts as a proving ground for the planned IceCube‑Gen2 facility, with additional calibration and prototype devices installed to validate next‑generation technologies under Antarctic conditions.