IceCube Upgrade

IceCube Upgrade
Name	IceCube Upgrade
Caption	The IceCube Neutrino Observatory surface lab at the Amundsen–Scott South Pole Station.
Experiment type	Neutrino detector upgrade
Location	South Pole, Antarctica
Institution	IceCube Collaboration
Energy range	GeV–TeV
Website	icecube.wisc.edu

IceCube Upgrade. The IceCube Upgrade is a major enhancement to the existing IceCube Neutrino Observatory, a cubic-kilometer neutrino detector embedded in the glacial ice at the South Pole. Scheduled for deployment in the mid-2020s, this upgrade will install new, advanced sensor modules within a dense infill array in the clearest ice beneath the original detector. Its primary objectives are to significantly improve the detector's calibration, enhance its low-energy neutrino detection capabilities, and serve as a critical technological pathfinder for the future, much larger IceCube-Gen2 observatory. The project is a cornerstone effort of the international IceCube Collaboration, involving dozens of institutions worldwide.

Overview

The IceCube Upgrade is designed as a high-density infill array within the deepest, clearest ice of the IceCube Neutrino Observatory. Situated directly below the center of the existing kilometer-scale grid, the upgrade will consist of seven new strings, each instrumented with multiple optical sensor modules. These strings will be deployed in boreholes drilled using the observatory's established hot-water drilling technology at the Amundsen–Scott South Pole Station. The new modules incorporate several generations of technological advancement over the original Digital Optical Modules, including improved photomultiplier tubes, advanced electronics, and new calibration devices. This dense configuration will transform a sub-volume of IceCube into a precision instrument for studying neutrino properties and interactions.

Scientific Goals

A primary scientific goal is the precise determination of neutrino oscillation parameters, particularly by measuring the disappearance of atmospheric muon neutrinos and the appearance of tau neutrinos. This will provide stringent tests of the three-flavor Standard Model of particle physics and probe for potential new physics. The upgrade will also enable detailed studies of neutrino cross-sections in the GeV energy range. Furthermore, its enhanced sensitivity will allow for a deeper search for sterile neutrinos and other exotic particles. The improved calibration from embedded light sources and other devices will reduce systematic uncertainties across all of IceCube's science, from astrophysical neutrinos to dark matter searches.

Technical Enhancements

The upgrade introduces new, multi-purpose optical modules, such as the multi-PMT D-Egg and the mDOM, which house multiple downward-facing and upward-facing photomultiplier tubes for increased angular coverage and sensitivity. Key technical enhancements include the deployment of calibrated light sources, like the Precision Optical Calibration Module, and acoustic sensors for monitoring ice properties. New electronics boards, developed in collaboration with institutions like the University of Wisconsin–Madison and the University of California, Berkeley, provide superior timing resolution and data acquisition capabilities. These technologies are direct precursors to those planned for the IceCube-Gen2 project.

Construction and Deployment

Construction of the sensor modules and associated hardware is distributed across the global IceCube Collaboration, with major assembly hubs at the University of Wisconsin–Madison and the DESY research center in Germany. Deployment will occur over a single Antarctic summer season, utilizing the existing South Pole logistics infrastructure managed by the United States Antarctic Program. The process involves melting boreholes with a custom hot-water drill, carefully lowering the instrumented strings, and allowing the ice to refreeze. Integration with the main IceCube Neutrino Observatory data stream will be managed through the central IceCube Lab.

Expected Timeline

Component production and testing began in earnest in the early 2020s. The shipment of all hardware to the South Pole is scheduled for the 2025-2026 austral summer. The in-ice deployment and commissioning phase is planned for the following 2026-2027 summer season, with full science operations expected to commence shortly thereafter. The data-taking period will overlap with the operations of the current IceCube detector and inform the final design of the IceCube-Gen2 observatory, which aims to begin construction later in the decade.

Collaboration

The project is undertaken by the international IceCube Collaboration, which includes over 300 scientists from more than 50 institutions across the globe. Leading institutions include the University of Wisconsin–Madison, the University of California, Berkeley, the University of Tokyo, the Stockholm University, and the RWTH Aachen University. Funding and logistical support are provided by agencies such as the National Science Foundation, the German Federal Ministry of Education and Research, the Swedish Research Council, and the Japan Society for the Promotion of Science.

Category:Particle physics experiments Category:Neutrino telescopes Category:Research stations in Antarctica